A mass of rock, bedrock, a large immovable stone. Distinguished from petros (a single stone). Jesus said He would build His church on 'this rock' — one of the most discussed statements in the NT.
Jesus declared: 'On this rock I will build my church' (Matthew 16:18). Whether the 'rock' is Peter's confession, Peter himself, or Christ, the point is clear: the church is built on an immovable, unshakeable foundation. Paul identifies Christ as 'the rock' that followed Israel in the wilderness (1 Corinthians 10:4). The wise man builds on rock, the fool on sand (Matthew 7:24-25).