Why is faith important for knowing we have eternal life?

1 John 2:3 highlights that we can know we are in Christ by keeping His commandments, which primarily means believing in Him. True faith is not about our works or the law but centers on the assurance that comes through trusting in the redemptive work of Christ. Belief in Him is the starting point for a relationship with God and signifies that we are alive spiritually. As we place our faith in Christ, we are reassured of our standing before God, enjoying the promise of eternal life secured by His sacrifice and our acceptance of it through faith.