The limit of carnal union "for the sake of begetting children" is established by matrimonial records; venial sin in its transgression.
From this, understand, my brothers, what Scripture felt about those of our parents who were married in such a way that they sought only offspring from their spouses. For they held themselves with such chastity, those who according to the custom and manner of their nation even had several [wives], that they approached carnal intercourse only for the purpose of procreation, truly holding them in honor. But whoever desires the flesh of a wife beyond that defined limit, for the purpose of begetting children, acts against the very contract by which he has taken her as a wife. The contract is read publicly in the sight of all the witnesses and it is read, "for the purpose of procreation of children"; and they are called marriage contracts. If wives are given and received for this purpose, who with a sound mind would give their daughter to another's lust? But so parents may not be embarrassed when giving, the contracts are read; so they are matchmakers, not pimps. What then is read from the contracts? "For the purpose of begetting children." The father's face is wiped and cleared, upon hearing the word of the contract. Let us observe the face of the husband receiving the wife. Let the husband be ashamed to take her otherwise, if the father is ashamed to give her otherwise. But if they cannot (as we have sometimes said before), let them demand the due; let them not go beyond what is due. Both the woman and the man must console themselves over their infirmity. Do not let him go to another, nor her to another: from which it is called adultery, as if with another. And if they go beyond the bounds of the marriage agreement, let them not go beyond the bounds of the matrimonial bed. Is it not a sin to demand from a spouse beyond the necessity for procreation of children? It is indeed a sin, but a venial one. The Apostle says: "But I say this by way of concession," when he said: "Do not deprive each other except by mutual consent for a time, so that you may devote yourselves to prayer; then come together again so that Satan will not tempt you because of your lack of self-control." What is this? Do not impose on yourselves more than you can bear; do not abstain from each other so long that you fall into adultery. Let Satan not tempt you because of your lack of self-control. And lest it seem he was commanding what he permitted (for it is one thing to command virtue, another to permit infirmity), he immediately adds: "I say this as a concession, not as a command." For I wish that all men were as I am. As if he said: I do not command you to act this way; but I forgive you if you do.
The human race stands on two supports.
Therefore, my brothers, pay attention. Those great men who had wives for the sake of procreating children, as we read the Fathers to have been, and we find by many proofs, the pages of Holy Scripture altogether undoubtedly declaring: if then there are men who have wives solely for the purpose of having children, if it could be given to them to have children without intercourse, would they not embrace such a benefit with ineffable joy? Would they not receive it with great happiness? For there are two bodily deeds by which the human race subsists: in which two deeds the wise and holy descend out of duty; the imprudent, however, rush into them out of desire. For it is one thing to descend into something out of duty, another thing to fall into something out of desire. What are these by which the human race subsists? First, in ourselves, what pertains to taking sustenance (which indeed cannot be taken without some delight through the flesh), eating and drinking: if you do not do this, you will die. Therefore, the human race stands by this one support, according to the measure of its nature, by eating and drinking. But by this support humans are sustained as far as it pertains to themselves: they do not ensure succession by eating and drinking; but by taking wives. For thus the human race consists, first so that men live: but because no care, however great, applied to the body can make them always live; the consequent provision is that those being born should succeed the dying. For so it is with the human race, as it is written, just as the leaves on a tree: but on an olive tree, or laurel, or some such tree, which is never without foliage; but still it does not always have the same leaves. For, as it is written, it generates some, and sheds others: because those which are newly sprouting, succeed the falling others. For it always sheds leaves, it is always clothed with leaves. Thus the human race daily does not feel the loss of the dying, due to the supplements of the newborn: and thus, according to its measure, the entire species of the human race subsists; and just as the leaves on a tree always seem to appear, so the earth full of humans is beheld. But if they only died, and were not born; like some trees stripped of all their leaves, so the earth would be stripped of all humans.
To the necessities of life, some are led by desire, others by reason.
Therefore, since the human race subsists in such a way that two supports are necessary, about which enough has been said; the wise, prudent, and faithful one descends to each duty, not falls due to lust. How many rush voraciously to eating and drinking, placing their whole life there, as if it were the very cause of living? For while they eat to live, they think they live to eat. Every wise person rebukes such people, especially the divine Scripture, calling them gluttons, drunkards, revelers, whose god is their belly. They are led to the table not by a desire for nourishment but by the lust of the flesh. Thus, they fall into food and drink. But those who descend due to the duty of living do not live to eat; rather, they eat to live. Therefore, if it were offered to these prudent and temperate ones to live without food and drink, with what joy would they embrace this favor, so that they would not be forced to descend or fall, but always remain uplifted in the Lord? Would not the necessity of sustaining the body's ruins cease to burden their intentions? How do you think the holy Elijah felt when he received the cup of water and the cake of bread, which was enough for him for the nourishment of forty days? Certainly, with great joy, for he ate and drank for the duty of life, not for the servitude of lust. Try to afford this, if you can, to a man who places all his happiness and bliss in feasting, like cattle in a stable. He hates your favor, rejects it, considers it a punishment. Thus also in that marital duty, lustful men seek wives for no other reason: and therefore they are scarcely content with even their own wives. And if they cannot or will not remove lust, they should not let it exceed what is prescribed by marital duty, even that which is conceded to weakness. But clearly, if you said to such a man, "Why do you take a wife?" he perhaps would answer you bashfully, "For the sake of children." If someone said to him, whom he would believe without any doubt, "God is able to give you children and will certainly give you children, even without performing that act with your wife," he would certainly be concluded and admit that he did not seek a wife for the sake of children. Let him therefore confess his weakness: let him accept what he pretended to accept for duty.
It was permitted for the fathers to have many wives for this reason only, that they might beget children.
Thus those former saints, men of God, sought sons, and wished to receive sons. For this purpose alone they joined with women; for this purpose they mingled with women, so that they might beget children. For this reason, it was permitted for them to have many [wives]. For if immoderate desire pleased God, it would be permitted at that time, so that one woman might have many husbands, just as one man could have many wives. Why did all chaste women not have more than one husband, and a man many wives: if not because one man having many wives is pertinent to the number of offspring; but one woman, no matter how many husbands she had, could not bear more children? Therefore, brothers, if our Fathers were joined and mingled with women for no other reason than to beget children; it would be a great joy for them, if besides that carnal work they could have children, for whose sake they did not rush into it out of lust, but descended from duty. For this reason, Joseph was not a father, because he received a son without carnal desire? Let it not be that Christian chastity thinks this, which even Judaic chastity did not think. Love your wives, but love them chastely. Seek the carnal work only to the extent that you may beget children. And because you cannot have children otherwise, descend to it with pain. For it is the punishment of that Adam, from whom we have descended. Let us not be proud about our punishment. It is the punishment of him who deserved to beget mortally; because through sin he became mortal. God did not take away that punishment; so that man would remember from where he is recalled, and to where he is called; and would seek that embrace, where no corruption can exist.
In that people, therefore, because an abundant propagation had to occur up to Christ, through the multitude of the people in which all the teachings that were to prefigure the Church were prefigured, they had the duty of taking wives through whom the people would grow, in which people the Church would be foreordained.
The dignity of virginity began from the Mother of the Lord. Joseph, how truly the father of Christ.
But when the King of all nations himself was born, the dignity of the virgin began with the Mother of the Lord, who both deserved to have a son and did not deserve to be corrupted. Thus, therefore, was that marriage, both a marriage without any corruption: thus the chaste wife gave birth, why wouldn't the husband also receive chastely? For just as that wife was chaste, so was that husband chaste: and just as that mother was chaste, so was that father chaste. Therefore, he who says: he should not be called father because he did not beget the son in that way; seeks lust in the procreation of children, not the affection of love. He more nobly fulfilled in spirit what another might desire to fulfill in the flesh. For those who adopt children also more purely generate them in their heart, whom they cannot in the flesh. See, brothers, see the laws of adoption, how a man becomes a son whose seed he was not born from; so that the will of the adopting exceeds the nature of the begetting. Therefore, Joseph not only ought to have been a father, but most certainly ought to have been. For even of women who are not wives, men generate children, and they are called natural children; and conjugal offspring are preferred to them. As far as the work of the flesh is concerned, they are equally born: wherefore do these offspring surpass the others, if not because the love of a wife from whom children are procreated is purer? There, the mingling of flesh is not regarded, which is equal in both women. Where does a wife surpass, if not in the affection of faith, the affection of marriage, the affection of purer and more chaste love? Therefore, if one could receive children from a wife without intercourse, would he not be all the more joyous, as she is chaster, whom he loves more?
Two fathers of Joseph are rightly admitted to reconcile Matthew and Luke.
Hence, now also see that it is possible for one man not only to have two sons, but also two fathers. For, with the mention of adoption, it may occur in your thoughts that it can happen. For it is said, "A man can have two sons, but he cannot have two fathers." Rather, it is found that he can also have two fathers; if one generates by seed, the other by adoption through affection. If then, one man can have two fathers, Joseph could have had two fathers, generated by one, adopted by the other. If this is possible, why do they criticize those who say that Matthew follows one genealogy, and Luke another? And indeed, we find that one follows one genealogy, the other another. For Matthew named Jacob as the father of Joseph. But Luke named Heli. And it can seem indeed that one man, whose son was Joseph, had two names. But because they enumerate different ancestors and forefathers and other progenitors, and in the very number one enumerates more, the other fewer; it is clearly shown that Joseph had two fathers. Now, the slander of the question removed, because clear reason demonstrated that it is possible for one father to generate and another to adopt; with two fathers established, it is not surprising if forefathers and great-grandfathers and other parents upwards are counted differently by different fathers.
Adoption in the Holy Scriptures. How intercourse with maidservants among the ancients was without adultery.
Nor should the right of adoption seem foreign to our Scriptures to you, as if observed in the practice of human laws, it cannot be congruent to the authority of divine Books. For it is an ancient matter, and customary in ecclesiastical sayings themselves, that not only the origin of seed generates a son, but also the grace of will. For even women adopted as sons those born from the seed of their husbands by handmaids, if they themselves had not given birth; indeed, they even commanded their husbands to father children for them: as Sarah, as Rachel, as Leah. In which duty, husbands did not commit adultery: because they obeyed their wives in that matter which pertains to conjugal duty; according to what the Apostle says: "The woman does not have authority over her own body, but the husband: likewise the husband does not have authority over his own body, but the wife." Moses also, born of a Hebrew mother and exposed, was adopted by Pharaoh's daughter. Indeed, those formulas of law which are now did not exist then: but the will's arbitration was held as the rule of law; as the Apostle also says elsewhere, because the Gentiles, not having the law, naturally do what is of the law. But if women were allowed to make sons of those whom they had not borne themselves; why not also men, of those whom they had not begotten themselves from carnal seed, but from the affection of adopting? For we read that Jacob the patriarch, the father of so many sons, nevertheless made his grandchildren, the sons of Joseph, his own sons, saying: "These two shall be mine, and they shall receive land with their brothers; those you shall have after them shall be yours." Unless perhaps someone should say that the very word 'adoption' is not found in the holy Scriptures. As if it matters by what term it is called, when it is the thing itself, that a woman should have a son whom she has not borne in the flesh; or a man someone whom he has not begotten in the flesh. And indeed, with me not opposing, let him not call Joseph adopted, provided he concedes that he could be indeed a son even of him from whose flesh he was not born. Although the Apostle Paul mentions even the name of adoption frequently, and in great sacrament. For when Scripture testifies that our Lord Jesus Christ is the only Son of God, it says that the brothers and co-heirs whom He deigned to have, are made by a certain adoption through divine grace. "But when the fullness of time had come," he says, "God sent forth his Son, born of woman, born under the law, to redeem those who were under the law, so that we might receive adoption as sons." And elsewhere: "We ourselves groan inwardly while we wait for adoption, the redemption of our bodies." Again, about the Jews he said: "I could wish that I myself were accursed and cut off from Christ for the sake of my brothers, my kinsmen according to the flesh. They are Israelites, and to them belong the adoption, the glory, the covenants, the giving of the law, the worship, and the promises; to them belong the patriarchs, and from their race, according to the flesh, is the Christ, who is God over all, blessed forever." Here he shows that the name or the thing itself of adoption was ancient among the Jews; like the testament and the giving of the law, which he mentions together.
The generations of the Lord are variously enumerated by the Evangelists without falsehood, considering the adoption or natural lineage.
To this it is added, because there was another method proper to the Jews by which someone would become the son of someone from whom he was not carnally born. For the relatives of their relatives who died without children used to take wives to raise up offspring for the deceased. Thus, he who was born was both the son of the one from whom he was born and the son of the one into whose succession he was born. These things are said so that no one might think it impossible, that the fathers of one man could be rightly mentioned by two people, and so accuse any one of the Evangelists who narrated the generations of the Lord with blasphemous slander as if accusing them of falsehood: especially as we see ourselves admonished by their very words. For Matthew, who is understood to mention him from whom Joseph was born, enumerates the generations in such a way, "He begat him," that he could arrive at what he says at the end: "Jacob begat Joseph." But Luke, because he is not properly called born who is made a son either by adoption or by birth in the succession of the deceased from her who was his wife, did not say, "Heli begat Joseph"; or, "Joseph whom Heli begat": but said, "Who was the son of Heli"; whether by adoption, or born from a relative in the succession of the deceased.
Why the generations are reckoned through Joseph and not through Mary.
But indeed, that question should not disturb us as to why the generations are counted through Joseph and not through Mary, has been sufficiently explained: because just as she was a mother without carnal desire, so he was a father without carnal union. Therefore, let the generations descend and ascend through him. Nor should we separate him for lack of carnal desire. The greater purity confirms his fatherhood: lest holy Mary herself reproach us. For she did not wish to place her name before her husband's, but said: “Your father and I have been looking for you sorrowing.” Therefore, let not the perverse murmurers do what the chaste spouse did not do. Let us count therefore through Joseph: because as he is a chaste husband, so is he a chaste father. But let us place the man before the woman by the order of nature and God's law. For if we set her in place, removing him, he would say, and rightly: “Why have you separated me? Why do not the generations ascend or descend through me? Will it be said to him, 'Because you did not beget by the work of your flesh?' But he will reply, 'Did she give birth by the work of her flesh?' What the Holy Spirit worked, He worked for both. 'Since he was a just man,' he says. A just man therefore, a just woman. The Holy Spirit resting in the justice of both, gave a son to both. But He worked in the sex that it was proper for giving birth, such that it would also be born to the husband. Thus, the angel says to both that they should name the child; where the authority of the parents is declared. For Zachariah, though still mute, the mother was naming the born son. And when those present signaled to the father what he wanted him to be called, having received writing tablets, he wrote what she had already said. It was said to Mary: “And behold, you will conceive in your womb and bear a son, and you shall call his name Jesus.” It was also said to Joseph: “Joseph, son of David, do not fear to take Mary as your wife, for that which is conceived in her is of the Holy Spirit. She will bear a son, and you shall call his name Jesus, for he will save his people from their sins.” It is also said: “And she bore a son to him,” where the father is firmly established not by the flesh, but by love. Thus he is a father. The Evangelists most cautiously and wisely count through him, whether Matthew, descending from Abraham to Christ, or Luke, ascending from Christ through Abraham to God. The one counts descending, the other ascending, both through Joseph. Why? Because father. Why father? Because the more firmly the father, the more chastely the father. Otherwise indeed, it was thought that he was the father of our Lord Jesus Christ, namely like other fathers begetting by flesh, not receiving children only by spiritual affection. For Luke also said: “He was supposed to be the father of Jesus.” Why was it supposed? Because human supposition and estimation led to what is usually done by humans. Therefore, the Lord is not from Joseph's seed, although this was supposed: and yet from the piety and love of Joseph, a son was born to Mary the virgin, who is also the Son of God.
Why does Matthew count descending, but Luke count ascending?
But why does he descending count, and why does the other ascending? Which, I ask, may you listen attentively, as much as the Lord has helped, now with a calm mind and free from all annoyance of knotty objections. Matthew descended through generations to signify our Lord Jesus Christ descending to bear our sins, so that in the seed of Abraham all nations might be blessed. Therefore, he does not begin from Adam: for all mankind is from him. Nor from Noah: because from his family, after the flood, all mankind sprang. Jesus Christ the man could not pertain to the fulfillment of prophecy from Adam, from whom all men are; nor from Noah, from whom all men again are; but from Abraham, who was then chosen in whose seed all nations would be blessed, when already the earth was full of nations. However, Luke ascends, not beginning to enumerate generations from the very origin of the birth of the Lord but from where he narrates him being baptized by John. Just as in the Lord's incarnation he takes on the sins of mankind to bear them, so in the consecration of Baptism for purification. Therefore, the one counting descending signifies descending to bear sins, enumerating generations downward: the other ascending, signifying the cleansing of sins, not his own certainly, but ours, enumerating generations upward. But the one descends through Solomon, in whose mother David sinned: the other ascends through Nathan, another son of the same David, by whom he was purified from sin. For we read that Nathan was sent to him, to rebuke him, and through repentance he was healed. Both met in David; he descending, the other ascending: and from there up to Abraham, or from Abraham up to David, in no generation are they different. Thus, Christ, both son of David and son of Abraham, goes to God. For to God indeed it is fitting that we, being renewed in Baptism from the abolition of sins, be brought back.
On the number forty in the generations of the Lord
Indeed, in the genealogies that Matthew enumerates, the number forty stands out. For divine Scriptures have this custom, that things which exceed certain numerical terms are sometimes not counted. Thus, also, it is said that four hundred years passed after which the people of Israel went out of Egypt, although it was four hundred and thirty. Similarly, one generation which exceeds the number forty does not take away the primacy of this number. This number, however, signifies the life in which labor is undergone on this earth, as long as we sojourn away from the Lord, in which the dispensation of proclaiming the truth temporally is necessary. For the number ten, which signifies the perfection of blessedness, multiplied four times for the reason of the fourfold time and the fourfold world, makes the number forty. Therefore, a fast of forty days was undertaken by Moses, by Elijah, and by our Mediator the Lord Jesus Christ himself, because in this time abstinence from bodily temptations is necessary. The people also sojourned in the desert for forty years; the flood occurred for forty days. For forty days after the resurrection, the Lord conversed with the disciples, persuading them of the truth of the risen body: where He signified in this life, in which we sojourn away from the Lord, what the number forty mystically suggests, as it has been said—namely, the necessary remembrance of the Lord’s Body, which we observe in the Church until He comes. Therefore, because our Lord descended into this life, and the Word was made flesh, to be delivered for our offenses and to rise again for our justification, Matthew followed the number forty: so that one generation which there exceeds the number forty, either does not impede, just as those thirty years do not impede the perfection of four hundred; or also signifies this, that the Lord himself, who when added makes forty-one, thus descended into this life to bear our sins, yet in this life, unique and singular in excellence, He is found to be set apart, as He is thus man while also being God. For it is said of this one alone, which could not or cannot be said of any other holy man, however perfect in wisdom and justice: the Word was made flesh.
Why does Luke count seventy-seven generations?
Luke, however, who ascends through generations from the baptism of the Lord, completes the number seventy-seven, beginning at our Lord Jesus Christ Himself, ascending through Joseph, and reaching God through Adam: that is, because in this number the abolition of all sins is signified, which is done in Baptism, not because it was something that needed to be forgiven in the Lord Himself, but because He, by His humility, commended what would be useful for us. And although it was the baptism of John, nevertheless, the Trinity of the Father, and the Son, and the Holy Spirit clearly appeared in it; through which the baptism of Christ Himself was consecrated, with which future Christians were to be baptized: the Father, in the voice that came from heaven; the Son, in the very man the Mediator; the Holy Spirit, in the dove.