St. Ambrose shows by instances that the places in which those words were spoken help to the understanding of the words of the Lord; he shows that Christ uttered the passage quoted from St. John in Solomon’s porch, by which is signified the mind of a wise man, for he says that Christ would not have uttered this saying in the heart of a foolish or contentious man. He goes on to say that Christ is stoned by those who believe not these words, and as the keys of heaven were given to Peter for his confession of them, so Iscariot, because he believed not the same, perished evilly. He takes this opportunity to inveigh against the Jews who bought the Son of God and sold Joseph. He explains the price paid for each mystically; and having in the same manner expounded the murmuring of the traitor concerning Magdalene’s ointment, he adds that Christ is bought in one way by heretics in another way by Catholics, and that those in vain take to themselves the name of Christians who sever the Spirit from the Father.