Text: Acts 3:19

In his second recorded gospel sermon, Peter told his audience to repent and be converted. What is conversion? In the New Testament, it is a change to follow Christ. In this lesson, we will notice three things that happen in our conversion – not just to see how conversion happens, but also to learn how to keep from reverting back to the world.

Change of Heart

  • Convert from unbelief to belief (John 20:27) – the Lord wants us to be firmly rooted and established in faith (Colossians 2:7)
  • Faith is essential for salvation (Hebrews 11:6) – God gave us the word so we can have faith (Romans 10:17); He does not expect us to have an irrational “faith,” but a reasonable faith (Hebrews 11:1); if we believe in Christ, we can have life (John 20:30-31)
  • We must not revert back to unbelief (Hebrews 3:12) – danger of being taken captive by other teachings (Colossians 2:8)
  • How to keep from reverting – regular encouragement (Hebrews 3:13); teaching and study (Romans 10:17)

Change of Life

  • Convert from worldliness to righteousness (Titus 2:11-14) – we are not to live as we once did (1 Peter 4:1-4)
  • Repentance is necessary for salvation (Luke 24:47) – taught by the apostles in carrying out the Great Commission (Acts 2:38; 3:19; 17:30); takes strong determination to repent (1 Corinthians 6:9-11; 1 Timothy 1:15-16); if we are not different from the world, we are useless to the Lord (Matthew 5:13)
  • We must not revert back to our old lives of sin (Romans 6:6, 11-12) – puts us in a worse condition (2 Peter 2:20-22; Hebrews 6:4-6)
  • How to keep from reverting – follow good examples (1 Peter 2:21; Philippians 3:17); practice virtues (2 Peter 1:5-10)

Change of State

  • Convert from being lost to being saved – from darkness to light (Acts 26:16-18; Colossians 1:13)
  • The change from a lost state to a saved state comes at the point of baptism (Mark 16:16) – parallel points in Peter’s first two sermons (Acts 2:38; 3:19); we must meet all of God’s conditions, but it is the work of God that saves (Colossians 2:12); this is why baptism is likened to an appeal (1 Peter 3:21)
  • There is a danger that Christians can revert back to the state of being lost (Hebrews 4:1, 11) – “once saved, always saved” is a comforting but false doctrine (Galatians 5:4)
  • How to keep from reverting – remember your commitment (1 Timothy 6:12-14); focus on the goal (Philippians 3:11-14)


  • In order to be saved, we need to be converted – change of heart, life, and state
  • If you have not been converted, or converted completely, now is the time to do it
  • If you have been converted and have reverted back to the world, now is the time to return

(Adapted from an outline by A.W. Dicus.)

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