The word Church means "called out ones."
The first time the Church is mentioned in Scripture is in Matt. 16:1818And I say also unto thee, That thou art Peter, and upon this rock I will build my church; and the gates of hell shall not prevail against it. (Matthew 16:18). Here it is the "house of God" with Christ as the builder. (Eph. 2:19-2219Now therefore ye are no more strangers and foreigners, but fellowcitizens with the saints, and of the household of God; 20And are built upon the foundation of the apostles and prophets, Jesus Christ himself being the chief corner stone; 21In whom all the building fitly framed together groweth unto an holy temple in the Lord: 22In whom ye also are builded together for an habitation of God through the Spirit. (Ephesians 2:19‑22); 1 Peter 2:4,54To whom coming, as unto a living stone, disallowed indeed of men, but chosen of God, and precious, 5Ye also, as lively stones, are built up a spiritual house, an holy priesthood, to offer up spiritual sacrifices, acceptable to God by Jesus Christ. (1 Peter 2:4‑5).) The "Rock" upon which it is built is Christ. (1 Cor. 10:44And did all drink the same spiritual drink: for they drank of that spiritual Rock that followed them: and that Rock was Christ. (1 Corinthians 10:4).)
When man builds, he has the warning as to bad material and its consequent judgment. (1 Cor. 3:9-179For we are laborers together with God: ye are God's husbandry, ye are God's building. 10According to the grace of God which is given unto me, as a wise masterbuilder, I have laid the foundation, and another buildeth thereon. But let every man take heed how he buildeth thereupon. 11For other foundation can no man lay than that is laid, which is Jesus Christ. 12Now if any man build upon this foundation gold, silver, precious stones, wood, hay, stubble; 13Every man's work shall be made manifest: for the day shall declare it, because it shall be revealed by fire; and the fire shall try every man's work of what sort it is. 14If any man's work abide which he hath built thereupon, he shall receive a reward. 15If any man's work shall be burned, he shall suffer loss: but he himself shall be saved; yet so as by fire. 16Know ye not that ye are the temple of God, and that the Spirit of God dwelleth in you? 17If any man defile the temple of God, him shall God destroy; for the temple of God is holy, which temple ye are. (1 Corinthians 3:9‑17).)
Peter does not get the keys of the Church, nor of heaven, but of "the kingdom of heaven." Thus Peter uses these keys to open the door of grace in the gospel to the Jews in Acts 2, and to the Gentiles in Acts 10. This, Peter refers to in respect of the Gentiles in Acts 15:77And when there had been much disputing, Peter rose up, and said unto them, Men and brethren, ye know how that a good while ago God made choice among us, that the Gentiles by my mouth should hear the word of the gospel, and believe. (Acts 15:7).
To be a "living stone," one must be born again, as Peter tells us in 1 Peter 1:2323Being born again, not of corruptible seed, but of incorruptible, by the word of God, which liveth and abideth for ever. (1 Peter 1:23). In Peter's second epistle, he shows the coming judgment upon those who are in the house; but not having life, they fall into corruption and are judged with the world.
May we be exercised to show the true character of God as His children!
ON CHRIST salvation rests secure;
The Rock of Ages must endure;
Nor can that faith be overthrown
Which rests upon the "Living Stone."
No other hope shall intervene:
To Him we look, on Him we lean:
Other foundations we disown,
And build on Christ, the "Living Stone."
In Him, it is ordained to raise
A temple to Jehovah's praise,
Composed of all the saints, who own
No Savior but the "Living Stone."
View the vast building, see it rise;
The work how great! the plan how wise!
O wondrous fabric! power unknown!
That rears it on the "Living Stone."
But most adore His precious Name;
His glory and His grace proclaim:
For us, condemned, despised, undone,
He gave Himself, the "Living Stone."