rock

Dictionary of Biblical Words:

This expression refers to the fact, that the Church which is Christ’s body (Eph. 1:2323Which is his body, the fulness of him that filleth all in all. (Ephesians 1:23)), instead of being one (John 17; Eph. 4:22With all lowliness and meekness, with longsuffering, forbearing one another in love; (Ephesians 4:2), &c.), is divided and split up into above 1,000 sects and parties. Of course the fact that al believers form one body cannot be destroyed (hence the “ruin of the body” would be incorrect), but the outward expression of this unity by a once united assembly or Church is gone entirely: hence the expression.

Concise Bible Dictionary:

Two words are principally employed for this word. One is sela, “an elevation of strength, immovable:” used symbolically for Jehovah as the rock of His people: “Jehovah is my rock and my fortress” (Psa. 18:22The Lord is my rock, and my fortress, and my deliverer; my God, my strength, in whom I will trust; my buckler, and the horn of my salvation, and my high tower. (Psalm 18:2)). He hath “set my feet upon a rock, and established my goings” (Psa. 40:22He brought me up also out of an horrible pit, out of the miry clay, and set my feet upon a rock, and established my goings. (Psalm 40:2)).
In the New Testament anyone who heard and did the sayings of the Lord is compared to a man who built his house upon the rock which nothing could shake (Matt. 7:24-2524Therefore whosoever heareth these sayings of mine, and doeth them, I will liken him unto a wise man, which built his house upon a rock: 25And the rain descended, and the floods came, and the winds blew, and beat upon that house; and it fell not: for it was founded upon a rock. (Matthew 7:24‑25); Luke 6:4848He is like a man which built an house, and digged deep, and laid the foundation on a rock: and when the flood arose, the stream beat vehemently upon that house, and could not shake it: for it was founded upon a rock. (Luke 6:48)). The Lord said, “Thou art Peter (πέτρος), and upon this rock (πέτρα) I will build My church.” The church is being built upon what Peter confessed, Christ Himself, the Son of the living God (Matt. 16:16-1816And Simon Peter answered and said, Thou art the Christ, the Son of the living God. 17And Jesus answered and said unto him, Blessed art thou, Simon Bar-jona: for flesh and blood hath not revealed it unto thee, but my Father which is in heaven. 18And 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 16:16‑18); compare 1 Cor. 3:1111For other foundation can no man lay than that is laid, which is Jesus Christ. (1 Corinthians 3:11); 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)).

Strong’s Dictionary of Greek Words:

Greek:
πέτρα
Transliteration:
petra
Phonic:
pet’-ra
Meaning:
feminine of the same as 4074; a (mass of) rock (literally or figuratively)
KJV Usage:
rock