Once, in perplexity, people asked Jesus, “What are we supposed to do?” (John 6:28). The Second Reading raises this question too.
The Second Reading says that if we don’t keep God’s commandments but say that we know the Lord, we are liars. In another passage from this Epistle (1 John 1:6-8), the author says that if we say we have no sin, we are liars, too. So thinking you know the Lord when you don’t keep the Lord’s commandments makes you a liar, and thinking you aren’t guilty of sin also makes you a liar.
What are we supposed to do?
When the people asked Jesus this question, he told them, “Believe on the one whom God has sent.” God sent Christ to be the expiation for our sins, the Epistle says. We are saved from our sins by him.
So we don’t have to be liars. We can tell the truth: we are sinful. But it doesn’t follow that we don’t keep God’s commandments. The Lord’s response to the people who asked him what we are supposed to do was a command: “Believe on the one whom God has sent.” And so it can be true both that we are sinful and that we keep the commandment of the Lord. If we believe that Jesus is the Savior, sent by God as the expiation for our sins, then, sinful as we are, we are still keeping the Lord’s commandment.
And if we keep his commandment, then it is also true that we know him. We know him not as a stern and baleful judge or as a lenient lover who doesn’t care what we do as long as we are happy. He is not either of these things. He is the Christ, the one sent by God to save us from our sins. When we sin, and if we aren’t liars trying to deny our sin, then he is there to save us. That is what it is for him to be the one sent by God, the Christ, the expiation of our sins.
And so this is what we are supposed to do: know him.