The promise thus emphatically made to Simon, "Thou shalt be called the Rock," our Lord fulfilled in the second year of His ministry, when He distinguished the twelve Apostles from the rest of His disciples, giving them authority to teach, and power to heal sicknesses and to cast out devils. Then, says S. Mark "to[21] Simon He gave the name of Peter;" and S. Matthew, "the names of the Twelve Apostles are these; the first, Simon, who is called Peter;" and S. Luke, "Simon whom also He named Peter." And by this name He marked Him out from amongst all his brethren, and united him to Himself. "He changes, too," says Tertullian, "Peter's name from Simon, because also as Creator He altered the names of Abraham, Sara, and Oshua, calling the last Jesus, and adding syllables to the others, but why did He call him Peter? If for the strength of his faith, many solid substances would lend him a name from themselves. Or was it because Christ is both the Rock and the Stone? Since we read that He is set for a stone of stumbling and a rock of offence. I omit the rest. And so it was His pleasure to communicate to the dearest of His disciples, in a peculiar manner, a name drawn from the figures of Himself, I imagine, as being nearer than one drawn from figures not of Himself."[22] It is, then, setting a seal on His former acts, drawing out and corroborating their meaning, that He once more, and in the most emphatic way of all, recurs to this name, attaching to it the most signal promises, and establishing its prophetic power. In the third year of His ministry our Lord "came into the quarters of Cesarea Philippi: and He asked His disciples, saying, Whom do men say that the Son of Man is? But they said, Some John the Baptist, and others Elias, and others Jeremias, or one of the prophets. Jesus saith to them, But whom say ye that I am? Simon Peter answered and said, Thou art Christ, the Son of the living God. And Jesus answering, said to him, Blessed art thou Simon Bar Jonas, because flesh and blood hath not revealed it to thee, but my Father who is in heaven. And I say to thee that thou art Peter; and upon this rock I will build my Church, and the gates of hell shall not prevail against it. And I will give to thee the keys of the kingdom of heaven. And whatsoever thou shalt bind on earth shall be bound also in heaven; and whatsoever thou shalt loose on earth, it shall be loosed also in heaven."