Meaning: Strength of an argument.
Psalm 31:2
Bow down thine ear to me; deliver me speedily: be thou my strong rock, for an house of defence to save me.
Matthew 7:24-25
Therefore whosoever heareth these sayings of mine, and doeth them, I will liken him unto a wise man, which built his house upon a rock: [25] And 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.
Luke 6:48
He 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.