Reprobation, in Christian theology, is a doctrine which teaches that a person can reject the gospel to a point where God in turn rejects them and curses their conscience. The English word reprobate is from the Latin root probare (English: prove, test), which gives the Latin participle reprobatus (reproved, condemned), the opposite of approbatus (commended, approved). The doctrine is first found in Jeremiah 6:30, but also found in many passages of scripture, such as Romans 1:20-28, 2 Corinthians 13:5-6, Proverbs 1:23-33, John 12:37-41, and Hebrews 6:4-8.

In Christian doctrine, when a sinner is so hardened as to feel no remorse or misgiving of conscience for particularly vile acts, it is considered a sign of reprobation. The doctrine does not stipulate that because of a reprobates' wicked deeds that God will not save them, but rather that God has effectively permanently withdrawn his offer of salvation by giving them over to a seared conscience, and now they are a reprobate capable of willingly committing these certain sins not common among mankind.