We need to beware of thinking that the Lord's commandments are unbearable burdnes. He hasn't laid upon us more than we can bear. Listen to John in this same epistle in 5:3 - "For this is the love of God, that we keep His commandments. And His commandments are not burdensome." God's expectations are neither unreasonable nor unbearable. Some seem to think that the commandments of God are a massive burden that we could never even comprehend, much less obey. It's easy as a preacher to bear down on the fact that if we love God, then we'll obey Him. But, I also need to help people see that God isn't requiring anything that is a grievous burden.
Let the Bible supply an illustration here. Paul wrote an epistle to the Philippian church. The church at Philippi was a good congregation. He says much to commend them. Still, they were not perfect. They were Christians, but they were still subject to failings of the flesh. They had weaknesses just like we do. Now keep that in mind while we look at what the apostle wrote to them in Philippians 2:12 - "Therefore, my beloved, as you have always obeyed, not as in my presence only, but now much more in my absence, work out your own salvation with fear and trembling." Notice how he worded it - "as you have always obeyed." Does this mean that they had never failed in any way? Does it mean that their obedience was perfect obedience? Of course not. The point to be emphasized is that the apostle could say that they were obedient even though they were not perfect! They were walking in the light; they were going in the right direction with the Lord.
The same point can apply to us today. We don't claim to be perfect. It would be foolish for us to think that we have obeyed everything flawlessly. Like the Philippians, however, we can say that our lives as Christians have been lives of obedience and that we are going to keep on working out our salvation with fear and trembling. "Now by this we know that we know Him, if we keep His commandments" (I John 2:3).
There should be no mystery about this. We can know what the Lord requires and we can know whether we have complied. The Bible shows us that we must have faith in Christ (cf. John 8:24; Heb. 11:6). I know I have such faith. Repentance is also required (cf. Luke 13:3; Acts 17:30), and I repented of my sins when I came to Christ (and I continue to turn from my sins even today). We are taught to confess our faith (cf. Rom. 10:9,10). Before I was baptized, I confessed that I believe that Jesus Christ is the Son of God, and I continue to endeavor to live consistently with that confession daily. I have no doubts about this and neither should anyone have any doubts as to whether he has been scripturally baptized. As it is commanded in Acts 2:38 (and elsewhere, e.g., Mark 16:15,16; Acts 22:16), I was immersed in the name of Christ for the remission of sins!
The same understanding goes along with the commandments that pertain to Christian living. There is no mystery as to whether one is living morally upright, whether he worships faithfully, whether he is living for the Lord. No, my Christian life is not without shortcomings; my obedience is always going to be imperfect obedience. But I know--and I think you know--the difference between living for the Lord and living for the devil. And as we continue to live for the Lord, we know that we know Him.
Dear friends, it is a wonderful thing to be a Christian. What we have highlighted in I John are the blessed assurances that if we are walking in the light, if we keep on confessing our sins, if we put our trust in our Advocate, and if we keep on living in faithful obedience, then there is not a single sin that will be held against us. That is blessed assurance! And that is the key to having confidence in your own salvation.