We live in a culture that places a high value on proof. If we are going to believe something, we must be convinced that it is true. Previously, John dealt with the issue of our continual battle with personal sin and our need to be in the habit of regular confession of sin. This correlates to the over all theme of 1 John which deals with the fellowship of joy. In order for our joy to be full we must be in perfect fellowship with the Lord and with each other. However, that fellowship is easily broken when we sin, thus, the need for confession and forgiveness.
The main issue in John’s day was the exodus of people leaving the church to follow worldliness and false doctrines. John is writing to those that remain to encourage them in their walk with God so that their fellowship could be strengthened and their joy full. In verse 3-6 of chapter 2, John identifies those who are truly in the light. He provides a comparison of those who remained faithful and those who have seemingly abandoned the faith and true doctrine. There is one underlining element that separates the sheep from the goats. There is one thing that is most certainly evident in someone who is truly in the light. There is one thing that is proof of genuine conversion. That one thing is: Keeping His Commandments. A life of obedience is the sure evidence of a life that has been glorious changed by the Gospel of Jesus Christ.
In this passage we see four basic things that keeping His commandments does for us. Understanding the benefits of keeping His commandments should compel us to walk in the light and thus have our joy full as our fellowship is strengthened.
Keeping His Commandments Provides Personal Assurance. 1 John 2:3 says, “And hereby we do know that we know him, if we keep his commandments.”What does it mean to know Him? How do we know Jesus? To know Jesus is to have a personal relationship with Him. It is to know Him as family. Knowing Him is not simply knowing things about Him or knowing Him as just another acquaintance. Knowing Jesus is not just being familiar with Him. “Knowing him is not knowing facts about him, nor simply being able to recognize him operating in circumstances or in other people; it is knowing him personally for oneself.” Knowing Jesus is having a real, tangible, and continual relationship with Him. To know Jesus in such a way we must believe in Him by faith. We must believe that Jesus died for our sins and rose again from the grave. We must believe that Jesus is God. We must believe that He was born of a virgin. To know Jesus, we must believe everything there is to know about Him. The act of believing comes through the avenue of faith. We must totally and completely trust in Him. We must trust in Him for our salvation and in every other aspect of our lives. How do we know that we truly know Him? If we keep His commandments. A life of obedience is the surest evidence of salvation. The New American Commentary says, “The condition put forth by John is that we can have assurance that we know “him” if we obey (keep) his commandments.” Many people struggle with the assurance of their salvation. The reason for this is because of their continual struggle to live a life of obedience. It is when we are changed on the inside that our behavior on the outside is transformed and we live in greater obedience which gives us the assurance and confidence that we are truly born-again. John says that it is possible for you to have 100% confidence that you are truly saved. It is possible to know for sure that you know Jesus. The condition to have such confidence is if you are keeping His commandments. If you are not keeping His commandments, then you do have every reason to doubt your salvation. If you are keeping His commandments, then all doubt is removed.
Keeping His Commandments Provides Cooperate Assurance. Verse 4 says, “He that saith, I know him, and keepeth not his commandments, is a liar, and the truth is not in him.”It is easy to spot a phony. Children are best at this. They know when you are not being real with them. They can tell if you really care for them and love them. No one really likes a phony; however, the church is plagued with them. There are many who say they know Jesus, yet, they have never known Him. Dr. David Walls writes the following:
“The religion that came to be known as Gnosticism prided itself in knowing God through mystical enlightenment, though that knowledge had no bearing on their moral behavior. They had no understanding that sin was a barrier to their relationship with God. John set them straight about this claim: “If you know God, you keep his commandments, and if you make no effort to keep his commandments, but still claim to be a Christian, you are a liar.”
This distinction is comforting when we look at extreme sin, assuming we are not involved in extreme sin. It makes it plain that those who clearly live like the devil can make no claim to be Christian. However, it is very discomforting when we consider more subtle sin. How obedient do we have to be? I violated one of God’s commands just last night. Am I a Christian, or am I a liar? Must we obey all commands perfectly? If that is the case, are any of us saved?
Clearly, the Bible is not saying that we have to exhibit perfect obedience. First John 1:8 just told us that if we claim to be without sin, we deceive ourselves and make God out to be a liar. The issue appears to be whether or not we take God’s commandments seriously and are trying to keep them. We may not keep them perfectly. We may not even have a perfectly consistent desire to keep them. But if we are truly born again, we will not live our lives in disregard for God’s commands. The Gnostics, it can be assumed, weren’t even trying to keep God’s commands.“
Those who blatantly refuse to live in obedience to Christ is certainly not a true a believer. A true believe may disobey and sin, but the overall pattern of the life of a true believe is moving toward greater obedience. If there is absolutely no pattern of obedience and no regard for the things of God, then it is impossible to say that you are a child of God. Years ago, I was counseling with someone on a particular issue. I opened the Bible and showed them exactly what God’s Word said concerning the issue. Their response was: “I don’t care what the Bible says, I am going to do what I want to do.” My friend, someone with such an attitude is not a true believer Christ. John makes it very clear that if you say you are in Christ, but you do not keep His commandments, you are a liar. We can ascertain someone’s true identity (believer or unbeliever) by whether or not they are keeping His commandments.
Keeping His Commandments Provides a Perfected Fellowship. We know that we are truly born again if the love of Christ is being perfected in us. Verse 5 says, “But whoso keepeth his word, in him verily is the love of God perfected: hereby know we that we are in him.” Our fellowship with the Lord is strengthened as we grow in Him. Consistent spiritual growth is the tell all sign that someone is genuinely saved. If you are not progressively moving toward greater holiness and Christ likeness, there is a good chance you have never come to faith in Him. As believers in Christ, our fellowship with God depends on our obedience in keeping His commandments. The Holman Concise Commentary says, “The revelation of God’s purity and holiness led John to emphasize that obedience to God’s commands provides fellowship with God. Those who would enjoy fellowship with God must follow in the love, holiness, and service that characterized Christ.” You cannot be in right standing with God and have God’s favor upon your life as a Christian if you are not moving toward holiness. Progressive Sanctification is the key to continual fellowship with God. “The meaning then is, that we perceive, or discern ourselves to be sincere believers, and consequently that Christ is both our Propitiation and Advocate, when it is become habitual and easy to us to obey his commandments.” Consider your life and your personal walk with God. Do you feel that you are growing? Are you closer to the Lord now than you were when you first believed? Obedience to the Lord is the path to a perfected fellowship with Him. To be in right fellowship with God, you must keep His commandments. It is only when we are in right fellowship with God that we can experience His best for us on a daily basis. You will never know what it is like to have God’s favor and blessing on your life unless you are consistently growing in your walk with Him. Such growth occurs when we value the time we spend with Him and when we are consistently feeding on His Word.
Keeping His Commandments Provides Consistency. “He that saith he abideth in him ought himself also so to walk, even as he walked.” When we keep His commandments it establishes consistency in our lives. The more we obey Him, the more like Him we will be. Our goal is to be more like Jesus every day. The stronger our fellowship is with Christ the more like Him we will behave. This does not mean we will never slip back into the ways of the world and find ourselves contending with our sin nature. The battle with sin will continue till our final redemption. However, the stronger our fellowship with the Lord, the more consistent our walk with Him will be. We may still struggle with sin, but the trajectory of our life will be headed in the direction of conformity to the image of Christ. Are you seeing consistent spiritual growth in your life? It is in keeping His commandments that such consistency is experienced.
In conclusion I would like to draw your attention to the following commentary:
“The point of the admonitions to be obedient, to live righteously or to follow the example of Jesus is not to get us to start doing a number of things simply for the sake of doing them. Rather such admonitions remind us that we have already charted a course for ourselves. As we walk in that course we are reminded to ask ourselves, do these actions belong in the circle of light? The key here is reflection. We are not to be made anxious, but are rather prodded to reflect on what we say and do, how we think, pray, spend our time and money, raise our children, treat our coworkers, spouses and neighbors. Our aim is to live for one master, God alone, in and with all that we do. That is walking as Jesus walked.” 
Is your aim to be just like Jesus? Examine your life and see if your fellowship with the Lord is where it ought to be. A joyful fellowship with the Lord and other believers can only come as we walk with Him daily and live in obedience to His Word.