Will you please explain Matt. 16:18, 19? What is the meaning of the Greek word from which "Peter" and "rock" are translated, also John 1:42? What are the keys of the kingdom of heaven? 1. Peter comes from petros, which means a stone or a mass of rock broken off from the great original rock. 2. "Rock" comes from petra, invariably translated "rock" throughout the New Testament, just as petros invariably has reference to Peter, a stone or mass of rock from the original rock. Peter had made a confession of Christ Jesus. Our Lord told him that that did not come of any wisdom which he possessed, but God had revealed it to him. And upon that rock, confession of Christ as Saviour, God would build His church. What the rock is is clearly shown in Deut. 32:4 and Ps. 18:31. "Who is God, save Jehovah? and who is a Rock, besides our God?" This very clearly shows that He only is the Rock. "His way is perfect." Again listen to the apostle Paul as to what the true foundation is: "For other foundation can no man lay than that which is laid, which is Jesus Christ." 1 Cor. 3:11. And Peter himself tells us very explicitly that believers are "living stones, are built up a spiritual house, to be a holy priesthood," but at the same time "the foundation Stone" is Christ Jesus, and He also is a "Rock of offense" to those who disbelieve. The word "rock" comes from petra, the same as in Matt. 16:18. See 1 Peter 2:4-8. 3. Keys are the things that open. The keys of the kingdom of heaven open the kingdom of heaven, and the kingdom of heaven is opened by faith in the Gospel of the Lord Jesus Christ. This Gospel was preached by Peter to the Jews on the Day of Pentecost. It was preached to Gentiles, Cornelius, the Roman centurion, by Peter. See Acts 2 and Acts 10. God chose Peter to present both, to the Jews and to the Gentiles this wonderful Gospel of which he had the keys. And so we read in Acts 15 the words of Peter himself: "Brethren, ye know that a good while ago God made choice among you, that by my mouth the Gentiles should hear the word of the Gospel, and believe. And God, who knoweth the heart, bare them witness, giving them the Holy Spirit, even as He did unto us." Acts 15:7, 8. But this did not elevate Peter above the other apostles; for at the very council in which Peter spoke these words, James himself presided, and Peter was there, as well as the other apostles. Upon the foundation of Christ Jesus and belief in that foundation God builds His church. It is not by any man or any men that the church is founded. It is founded by the power of God Himself through that Son who has given His life to redeem mankind. Every one who believes in Him is as Peter was, a living stone built upon that foundation.