Chapter VIII.
Why is Psalm 50 placed before some other compositions and what mysteries are contained in its fiftieth number? How does the example of David teach us to perform penance and how can one be cleansed from wickedness in various ways?
But now let him defend himself, for he has written the fiftieth psalm about this story. And when he has included the history of his previous actions, such as the treachery of Doeg the Syrian, which is the title of the fifty-first psalm, and the attacks of the Ziphites, which seems to be included in the title of the fifty-third psalm; he has included this history that comes later, when Doeg had betrayed before, or the Ziphites, before the prophet David assumed his kingdom. Since he, fleeing King Saul, was still wandering in various hidden places as an exile; but when Bathsheba began to reign, he acquired it.
Why, then, does the order of the psalms not match the order of the events? Because it was intended to match not the order to the order, but the mystery to the events; and therefore, it wanted to assign the number of remission to this history. For the number fifty is the number of remission, as the Lord himself taught us in the Gospel, saying: There were two debtors to a certain moneylender; one owed five hundred denarii, the other fifty; since they had no way of repaying, he forgave both. Who then loves him more (Luke 7:41 and 42)? And in the Law you have (Leviticus 25:10 and following), because the jubilee is called the recurrence of fifty years, to be celebrated in a very special way, by which debts are canceled, the liberties of the Hebrews are confirmed, and possessions are restored. We celebrate this number joyfully after the Lord's passion, with the complete forgiveness of all guilt, and also with the cancellation of the handwriting, we are set free from every bond; and we receive the coming grace of the Holy Spirit on the day of Pentecost: fasting is set aside, praise is given to God, and alleluia is sung. Finally (36, quaest. 2, cap. Finally), and the father of the girl who, by force, having been betrothed to no one, endured fifty silver didrachms, she herself, however, will remain in marriage (Deut. XXII, 29). Therefore, by this number, even vices are transformed into favor. Therefore, a great psalm, by which we are taught how repentance should be practiced.
Have mercy upon me, O Lord, according to thy great mercy. And according to the multitude of thy tender mercies, blot out my iniquity. Wash me thoroughly from my iniquity, and cleanse me from my sin. For I acknowledge my iniquity, and my sin is always before me. Against thee only have I sinned, and done evil in thy sight; that thou mayest be justified in thy words, and overcome when thou art judged. For behold I was conceived in iniquities; and in sins did my mother conceive me. (Psalm 50:3 and following) Who among us, even if he confesses his sin, would rather not be reproved than repeated? Who would repent a second or third time? See how the great Prophet echoes his own sin in so many verses, how no verse is without the confession of a transgression. He confesses everything together, his iniquities and injustice, by personifying them, linking his sins to sins; and by frequently repeating them, he rightly demands great mercy; not only great mercy, but also a multitude of mercies. Therefore, does not such lamentation wash away sin, which kind of supplication does not cleanse guilt? He prays for the multitude of sins for one offense: we, for many sins, can scarcely believe that his mercy is to be besought even once. Then we read (Psalm 135:11 and 12) that in his great power and his exalted arm he delivered his people from the land of Egypt, when he led them across the Red Sea, in which was a figure of baptism. Therefore, if great virtue was in the form of the sacraments, how much greater is their mercy in truth? Also, rightly is there a multitude of mercies sought where there is a multitude of sinners.
Wash me thoroughly from my iniquity, and cleanse me from my sin (Psalm 50:4). He seeks to be washed not so much often as completely, so that he may wash away the accumulated filth. He knew that according to the Law there were many means of cleansing, but none that were full and perfect. Therefore, he hastens with his whole intention to that which is perfect, where all righteousness is fulfilled, which is the sacrament of Baptism, as the Lord Jesus himself teaches. For when he came to John, John said to him: I ought to be baptized by you, and yet you come to me (Matthew 3:14). Jesus answered: Let it be so for now; for thus it is fitting for us to fulfill all righteousness (ibid., 15). But after Christ was baptized, and the Holy Spirit descended upon him like a dove, and the Father sealed the Son from heaven, all righteousness was fulfilled. Therefore the Prophet says: Wash me thoroughly from my iniquity. For great filth and stain are removed not by a small, but by a large lavacro.
But if someone wants to receive it differently, they can shape their understanding in this way; divine speech purifies, our confession purifies; while it is heard, while it is uttered; good thought purifies, honest action purifies, good use of conversation also. Each person, purified by these things, more easily drinks them in and as if draws into themselves the splendor of spiritual grace. In the end, not by one infusion does the precious juice immediately radiate from the fleece, but first the fleece is stained with unholy juice; then it frequently washes away its natural appearance with other and other juices, and is often changed by different colors; and thus afterwards it is applied as a more complete dye, so that the truer and more perfect brilliance of purple may burst forth. Just as in the infection of purple, there is a multitude of thorns, so in the bath of regeneration, there is a multitude of heavenly mercies, so that wickedness may be removed. Therefore, one who is deeply washed is cleansed from injustice and from sin, and sets aside a certain inclination to sin in thoughts and habits, and forgets its nature. And one is cleansed well from injustice or iniquity, which is greater: one is also cleansed from sin, which is lesser.