"By this we know that we love the children of God, when we love God, and keep his commandments. For this is the love of God, that we keep his commandments: and His commandments are not burdensome." (1 John 5:2-3)
Right off the bat people make an assumption about which commands John was talking about. They assume it includes either all of the commands of the old covenant, or the 10 commandments, or the 2 greatest old covenant commandments Jesus identified, or every command Jesus ever spoke (regardless of who He spoke it to), or every command in the New Testament, or even every command in all of scripture.
1 John 5:3 says, "his commandments are not burdensome." This tells us right away that John is not including the commands of the old covenant. How do we know this? From what happens in Acts 15.
Some of the sect of the Pharisees who had trusted stood up, saying, “The Gentiles must be circumcised and required to keep the law of Moses.” The apostles and older men met to consider this question. After much discussion, Peter got up and addressed them:
“Brothers, you know that some time ago God made a choice among you that the Gentiles might hear from my lips the message of the gospel and trust. God, who knows the heart, showed that he accepted them by giving the Holy Spirit to them, just as he did to us. He did not discriminate between us and them, for he purified their hearts by trust. Now then, why do you try to test God by putting on the necks of Gentiles a yoke that neither we nor our ancestors have been able to bear? No! We trust it is through the grace of our Lord Jesus that we are saved, just as they are.” (Acts 15:5-11)
Here in the narrative of Acts Peter clearly says that Gentile Christians are not required to keep the law of Moses (including the 611 commands in it which includes the 10 commandments & the 2 greatest commandments). Peter points out that neither the Apostles, prophets, nor any Jew in history was able to bear the yoke of the law. Peter also said that it is testing God to require people to keep the law.
John was almost certainly there when this happened in Acts 15. Peter said all of the law of Moses was burdensome (unbearable) thus the commands John refers to in 1 John 5 could not have included any of those laws, 2 of which are the "love God with all that you are" & "love your neighbor as yourself" commands. Colossians 2:14, Ephesians 2:15 say the old covenant commands were "against us" & "stood opposed to us." Galatians 5:1 calls the law a yoke of slavery that Christ set us free from.
What Were the Commands?
John tells us earlier in his letter what the "commands" he speaks of in 1 John 5 are. In 1 John 3:23 he says, "This is God's command: to trust in the name of his Son, Jesus Christ, and to love one another as he commanded us." "As he commanded us" is "To love one another as He has loved us" (John 13:34). The commands he speaks of in 1 John 5 are "Trust Jesus" & "love one another as Jesus has loved us."
But John says, His commands aren't burdensome. He doesn't say the commands are unheavy burdens or light burdens. He says they aren't burdensome at all. How can that be? Are we supposed to "be good Christians" by pretending that they don't burden us? The mere fact that something is a command makes it burdensome. Well they are burdens but the burdens are carried by Christ not us! These commands are based on His love & His trustworthiness not upon our performance. While they are burdens, so to speak, they are not burdensome because the easiest thing ever for God to do is to be trustworthy & loving.
Galatians 5:6 says, "The only thing that counts is trust being expressed through love." The only thing that counts is trust in Jesus being expressed through loving actions by God in you. This is the natural product of trusting Jesus thus "His commands are not burdensome" (1 John 5:3). Our trust in Him naturally expresses love because He is the vine, He produces the love and love comes out of us as we trust Him. We don't need commands to tell us to love. We have LOVE HIMSELF living inside of us.
In John 6:28-29 some people asked Jesus, "What do we do to perform God's works?" Jesus told them, "This is the only work God wants from you: Trust in the one he has sent." This is deeply true. Trust is the only thing you have to do, everything else is done by God through you because you trust Him! Why do we trust Him? Because He loves us! How much does God love us? John 17:20-23 & 15:9 tells us The Father loves us just as much as He loves Jesus! Jesus loves us just as much as the Father loves Him!
If you love Me, you will keep My commandments † I Will Love You So You Will Trust Me
Trust and Love, Everything We Need