Conviction is the Holy Spirit’s application of the gospel to the human will, exposing sin and pressing home the truth of Christ.
Through the truth concerning Christ, the Spirit convinces the world of sin, of righteousness, and of judgment; He exposes the hearer’s guilt and false confidence and presses upon him his need of the Saviour. Because conviction works through the gospel, apart from that word there may be regret, shame, or sorrow, but not the Spirit’s saving conviction concerning Christ.
Conviction is not itself conversion. It is the Spirit’s pressure that drives a sinner toward repentant faith.
See in Scripture: John 16:7–11; Acts 2:37; Romans 3:19–20; 2 Corinthians 7:9–10