The Greek verb kataginōskō is a compound of kata- (against) and ginōskō (to know), meaning to judge against, to find guilty, to condemn, or to blame. It occurs 3 times in the New Testament — once in Galatians and twice in 1 John — always in the context of conscience, judgment, and condemnation.
In Galatians 2:11, Paul says Peter 'stood condemned' (kategnōsmenos) — his own actions bearing witness against him. The word appears most powerfully in 1 John 3:20–21 in a passage of great pastoral encouragement: 'If our hearts condemn (kataginōskō) us, God is greater than our hearts, and he knows everything. Dear friends, if our hearts do not condemn us, we have confidence before God.' John addresses the tender conscience — those plagued by self-accusation — with the assurance that God's knowledge surpasses even what our own hearts accuse us of. The believer's standing before God is not determined by the severity of their internal condemnation but by the sufficiency of Christ's atonement.