We can have assurance that we know God and are saved by God by looking at our faithful obedience to God.
1. Our obedience to God reveals if our faith in Jesus is genuine or not (verse 3-4).
“Knowledge of God is a robust concept that covers not only what you know about God, but also includes a personal relationship with God that begins with faith. It also includes an ever-deepening relationship and fellowship with God that is evidenced by love for him and obedience to God’s commands.” —David Allen
“One of the ways you know you are a Christian is if you desire to obey God. If you have no interest in doing what God says, if God’s principles and commandments are of little importance to you, that should be a red flag that you may not be a Christian. Assurance or your salvation is unattainable without obedience to God’s commands.” —David Allen
2. Our obedience to God reveals a mature love for God (verses 5-6).