Psalms 78:15

"He that burst asunder the rock in the desert, and gave them water as in a great deep" [Psalm 78:15]; "and brought out water from the rock, and brought down waters like rivers" [Psalm 78:16], is surely able upon thirsty faith to pour the gift of the Holy Spirit (the which gift the performance of that thing did spiritually signify), to pour, I say, from the Spiritual Rock that followed, which is Christ: who stood and cried, "If any is thirsty, let him come to Me:" [John 7:37] and, "he that shall have drunk of the water which I shall give, rivers of living water shall flow out of his bosom." [John 4:14] For this He spoke, as is read in the Gospel, [John 7:39] to the Spirit, which they were to receive that believed in Him, unto whom like the rod drew near the wood of the Passion, in order that there might flow forth grace for believers.

"He split the rock in the desert." The rock has been split for us in the wilderness. The rock was struck, and the waters flowed: that rock which says, "Whoever thirsts, let him come and drink"; from whose belly rivers flowed. "And he gave them water to drink as if from a great abyss." In the desert, where there was no water, an abundance of waters was made for us. There are many things that might be said, and the psalm is boundless, and we are shut out by time. But let us pray the Lord that for us too he may split the sea, that for us too the rock may pour out waters, lest our corpses too perish and lie with the people in the desert. For you know that the corpses of our fathers lie in the desert to this day. Believe me: as often as I see synagogues, I always have in my mind that which is said by the apostle, that we ought not to exult over the olive tree whose branches were broken, but to fear; since if the natural branches were cut off, how much more should we, who are grafted in from the wild olive, fear lest we become like our fathers, "a generation crooked and provoking, a generation which did not direct its heart, and whose spirit was not held faithful with God." Since they do not have the Spirit of God, therefore they are dead, and their corpses lie in the desert. I understand their synagogues to be nothing else but tombs in the desert. Read the old books. But let us pray the Lord that these tombs too may rise again. For if the children of Abraham have been made from stones, the children of Adam, who are dead, can rise again, if Jesus wills it. For although they are dead and lie in tombs, even if they are four days dead, even if they stink, Jesus can say to them: "Lazarus, come forth."