of God[1] in word, and in deeds, and in the power of signs and wonders, in the power of the Holy Spirit. And so I have preached this Gospel not where Christ was already known, that I might not build upon another man's foundation," Romans 15:18–20. Was not this that apostle, a vessel of election, who said he did not dare to preach anything save those things which Christ spoke through him; for otherwise he would not be building on Christ, the most effectual foundation, if perchance he should say and teach or do anything which did not have its foundation in Jesus Christ. And from this it is plain, that not Peter but the Rock, Christ, was intended in Christ's Gospel, when Christ said: "On this Rock I will build my church."
But the objection is drawn from Ambrose, Dist. 50 [Friedberg, 1: 198], where he says: "Peter became more faithful after he had wept over having relinquished his faith and so he found greater grace than he lost. For as a good shepherd he received the flock to care for it so that, as he had been weak to himself, he might become a buttress—firmamentum—to all, and he who faltered,[2] under the temptation of a question, might establish others by the steadfastness of his faith. Finally, in order to strengthen the devotion of the churches, he was called rock, as the Lord said: 'thou art Peter and upon this rock I will build my church.' For he is called petra—rock—because he was to be the first to lay the foundations of the faith among the nations,[3] and, as an immovable bowlder—saxum—he held up the structure and weighty edifice of the whole of Christ's work." So much Ambrose, showing that Peter is called the rock. The exposition of Augustine, the foremost of Scripture expositors, seems to me here to be more efficacious and is more efficacious because it
