17 But there is in some copies, “For I have not known literature.” Where some books have “trading,” there others “literature:” how they may accord is a hard matter to find out; and yet the discrepancy of interpreters perchance shows the meaning, introduces no error. Let us inquire then how to understand literature also, lest we offend grammarians in the same way as we did traders a little before: because a grammarian too may live honourably in his calling, and neither forswear nor lie.
Let us examine then the literature which he has not known, in whose mouth all the day long is the praise of God. There is a sort of literature of the Jews: for to them let us refer this; there we shall find what has been said: just as when we were inquiring about traders, on the score of actions and works, we found that to be called detestable trading, which the Apostle has branded, saying, “For being ignorant of God's righteousness, and willing to establish their own, to the righteousness of God they were not made subject.”...Just as then we found out the former charge against traders, that is men boasting of action, exalting themselves because of business which admits no inaction, unquiet men rather than good workmen; because good workmen are those in whom God works; so also we find a sort of literature among the Jews....Moses wrote five books: but in the five porches encircling the pool, sick men were lying, but they could not be healed.
See how the letter remained, convicting the guilty, not saving the unrighteous. For in those five porches, a figure of the five books, sick men were given over rather than made whole. What then in that place did make whole a sick man? The moving of the water. When that pool was moved there went down a sick man, and there was made whole one, one because of unity: whatsoever other man went down unto that same moving was not made whole. How then was there commended the unity of the Body crying from the ends of the earth?
Another man was not healed, except again the pool were moved. The moving of the pool then did signify the perturbation of the people of the Jews when the Lord Jesus Christ came. For at the coming of an Angel the water in the pool was perceived to be moved. The water then encircled with five porches was the Jewish nation encircled by the Law. And in the porches the sick lay, and in the water alone when troubled and moved they were healed. The Lord came, troubled was the water; He was crucified, may He come down in order that the sick man may be made whole.
What is, may He come down? May He humble Himself. Therefore whosoever ye be that love the letter without grace, in the porches you will remain, sick ye will be, lying ill, not growing well....For the same figure also it is that Eliseus at first sent a staff by his servant to raise up the dead child. There had died the son of a widow his hostess; it was reported to him, to his servant he gave his staff: go thou, he says, lay it on the dead child. Did the prophet not know what he was doing?
The servant went before, he laid the staff upon the dead, the dead arose not. “For if there had been given a law which could have made alive, surely out of the law there had been righteousness.” The law sent by the servant made not alive: and yet he sent his staff by the servant, who himself afterwards followed, and made alive. For when that infant arose not, Eliseus came himself, now bearing the type of the Lord, who had sent before his servant with the staff, as though with the Law: he came to the child that was lying dead, he laid his limbs upon it.
The one was an infant, the other a grown man: he contracted and shortened in a manner the size of his full growth, in order that he might fit the dead child. The dead then arose, when he being alive adapted himself to the dead: and the Master did that which the staff did not; and grace did that which the letter did not. They then that have remained in the staff, glory in the letter; and therefore are not made alive. But I will to glory concerning Your grace....In that same grace I glorying “literature have not known:” that is, men on the letter relying, and from grace recoiling, with whole heart I have rejected.
Source: The Enarrations, or Expositions, on the Psalms (New Advent)