Reply to Objection 1: That which is both sacrament and reality---i.e. the character---and that which is reality only---i.e. the inward justification---remain: the character remains and is indelible, as stated above (Q[63], A[5]); the justification remains, but can be lost. Consequently Damascene defined Baptism, not as to that which is done outwardly, and is the sacrament only; but as to that which is inward. Hence he sets down two things as pertaining to the character---namely, "seal" and "safeguarding"; inasmuch as the character which is called a seal, so far as itself is concerned, safeguards the soul in good. He also sets down two things as pertaining to the ultimate reality of the sacrament---namely, "regeneration" which refers to the fact that man by being baptized begins the new life of righteousness; and "enlightenment," which refers especially to faith, by which man receives spiritual life, according to Habac 2 ( Heb. 10:38 ; cf. Habac 2:4 ): "But (My) just man liveth by faith"; and Baptism is a sort of protestation of faith; whence it is called the "Sacrament of Faith." Likewise Dionysius defined Baptism by its relation to the other sacraments, saying (Eccl. Hier. ii) that it is "the principle that forms the habits of the soul for the reception of those most holy words and sacraments"; and again by its relation to heavenly glory, which is the universal end of all the sacraments, when he adds, "preparing the way for us, whereby we mount to the repose of the heavenly kingdom"; and again as to the beginning of spiritual life, when he adds, "the conferring of our most sacred and Godlike regeneration."
Reply to Objection 2: As already stated, the opinion of Hugh of St. Victor on this question is not to be followed. Nevertheless the saying that "Baptism is water" may be verified in so far as water is the material principle of Baptism: and thus there would be "causal predication."
Reply to Objection 3: When the words are added, the element becomes a sacrament, not in the element itself, but in man, to whom the element is applied, by being used in washing him. Indeed, this is signified by those very words which are added to the element, when we say: "I baptize thee," etc.
Whether Baptism was instituted after Christ's Passion?
Objection 1: It seems that Baptism was instituted after Christ's Passion. For the cause precedes the effect. Now Christ's Passion operates in the sacraments of the New Law. Therefore Christ's Passion precedes the institution of the sacraments of the New Law: especially the sacrament of Baptism since the Apostle says ( Rom. 6:3 ): "All we, who are baptized in Christ Jesus, are baptized in His death," etc.
Objection 2: Further, the sacraments of the New Law derive their efficacy from the mandate of Christ. But Christ gave the disciples the mandate of Baptism after His Passion and Resurrection, when He said: "Going, teach ye all nations, baptizing them in the name of the Father," etc. ( Mat. 28:19 ). Therefore it seems that Baptism was instituted after Christ's Passion.
Objection 3: Further, Baptism is a necessary sacrament, as stated above (Q[65] , A[4]): wherefore, seemingly, it must have been binding on man as soon as it was instituted. But before Christ's Passion men were not bound to be baptized: for Circumcision was still in force, which was supplanted by Baptism. Therefore it seems that Baptism was not instituted before Christ's Passion.
On the contrary, Augustine says in a sermon on the Epiphany (Append. Serm., clxxxv): "As soon as Christ was plunged into the waters, the waters washed away the sins of all." But this was before Christ's Passion. Therefore Baptism was instituted before Christ's Passion.
I answer that, As stated above (Q[62], A[1]), sacraments derive from their institution the power of conferring grace. Wherefore it seems that a sacrament is then instituted, when it receives the power of producing its effect. Now Baptism received this power when Christ was baptized. Consequently Baptism was truly instituted then, if we consider it as a sacrament. But the obligation of receiving this sacrament was proclaimed to mankind after the Passion and Resurrection. First, because Christ's Passion put an end to the figurative sacraments, which were supplanted by Baptism and the other sacraments of the New Law. Secondly, because by Baptism man is "made conformable" to Christ's Passion and Resurrection, in so far as he dies to sin and begins to live anew unto righteousness. Consequently it behooved Christ to suffer and to rise again, before proclaiming to man his obligation of conforming himself to Christ's Death and Resurrection.
Reply to Objection 1: Even before Christ's Passion, Baptism, inasmuch as it foreshadowed it, derived its efficacy therefrom; but not in the same way as the sacraments of the Old Law. For these were mere figures: whereas Baptism derived the power of justifying from Christ Himself, to Whose power the Passion itself owed its saving virtue.
Reply to Objection 2: It was not meet that men should be restricted to a number of figures by Christ, Who came to fulfil and replace the figure by His reality. Therefore before His Passion He did not make Baptism obligatory as soon as it was instituted; but wished men to become accustomed to its use; especially in regard to the Jews, to whom all things were figurative, as Augustine says (Contra Faust. iv). But after His Passion and Resurrection He made Baptism obligatory, not only on the Jews, but also on the Gentiles, when He gave the commandment: "Going, teach ye all nations."
Reply to Objection 3: Sacraments are not obligatory except when we are commanded to receive them. And this was not before the Passion, as stated above. For our Lord's words to Nicodemus ( Jn. 3:5 ), "Unless a man be born again of water and the Holy Ghost, he cannot enter into the kingdom of God, seem to refer to the future rather than to the present."
Whether water is the proper matter of Baptism?
Objection 1: It seems that water is not the proper matter of Baptism. For Baptism, according to Dionysius (Eccl. Hier. v) and Damascene (De Fide Orth. iv), has a power of enlightening. But enlightenment is a special characteristic of fire. Therefore Baptism should be conferred with fire rather than with water: and all the more since John the Baptist said when foretelling Christ's Baptism ( Mat. 3:11 ): "He shall baptize you in the Holy Ghost and fire."
Objection 2: Further, the washing away of sins is signified in Baptism. But many other things besides water are employed in washing, such as wine, oil, and such like. Therefore Baptism can be conferred with these also; and consequently water is not the proper matter of Baptism.
Objection 3: Further, the sacraments of the Church flowed from the side of Christ hanging on the cross, as stated above (Q[62], A[5]). But not only water flowed therefrom, but also blood. Therefore it seems that Baptism can also be conferred with blood. And this seems to be more in keeping with the effect of Baptism, because it is written ( Apoc. 1:5 ): "(Who) washed us from our sins in His own blood."
Objection 4: Further, as Augustine (cf. Master of the Sentences, iv, 3) and Bede (Exposit. in Luc. iii, 21) say, Christ, by "the touch of His most pure flesh, endowed the waters with a regenerating and cleansing virtue." But all waters are not connected with the waters of the Jordan which Christ touched with His flesh. Consequently it seems that Baptism cannot be conferred with any water; and therefore water, as such, is not the proper matter of Baptism.
Objection 5: Further, if water, as such, were the proper matter of Baptism, there would be no need to do anything to the water before using it for Baptism. But in solemn Baptism the water which is used for baptizing, is exorcized and blessed. Therefore it seems that water, as such, is not the proper matter of Baptism.
On the contrary, our Lord said ( Jn. 3:5 ): "Unless a man be born again of water and the Holy Ghost, he cannot enter into the kingdom of God."
I answer that, By Divine institution water is the proper matter of Baptism; and with reason. First, by reason of the very nature of Baptism, which is a regeneration unto spiritual life. And this answers to the nature of water in a special degree; wherefore seeds, from which all living things, viz. plants and animals are generated, are moist and akin to water. For this reason certain philosophers held that water is the first principle of all things.
Secondly, in regard to the effects of Baptism, to which the properties of water correspond. For by reason of its moistness it cleanses; and hence it fittingly signifies and causes the cleansing from sins. By reason of its coolness it tempers superfluous heat: wherefore it fittingly mitigates the concupiscence of the fomes. By reason of its transparency, it is susceptive of light; hence its adaptability to Baptism as the "sacrament of Faith."
Thirdly, because it is suitable for the signification of the mysteries of Christ, by which we are justified. For, as Chrysostom says (Hom. xxv in Joan.) on Jn. 3:5, "Unless a man be born again," etc., "When we dip our heads under the water as in a kind of tomb our old man is buried, and being submerged is hidden below, and thence he rises again renewed."
Fourthly, because by being so universal and abundant, it is a matter suitable to our need of this sacrament: for it can easily be obtained everywhere.
Reply to Objection 1: Fire enlightens actively. But he who is baptized does not become an enlightener, but is enlightened by faith, which "cometh by hearing" ( Rom. 10:17 ). Consequently water is more suitable, than fire, for Baptism.
But when we find it said: "He shall baptize you in the Holy Ghost and fire," we may understand fire, as Jerome says (In Matth. ii), to mean the Holy Ghost, Who appeared above the disciples under the form of fiery tongues ( Acts 2:3 ). Or we may understand it to mean tribulation, as Chrysostom says (Hom. iii in Matth.): because tribulation washes away sin, and tempers concupiscence. Or again, as Hilary says (Super Matth. ii) that "when we have been baptized in the Holy Ghost," we still have to be "perfected by the fire of the judgment."