But whoever obeys his word, truly in this person the love of God has reached perfection. By this we may be sure that we are in him. (1 John 2:5)
This verse should probably be taken in context (vv 1-6):
My little children, I am writing these things to you so that you may not sin. But if anyone does sin, we have an advocate with the Father, Jesus Christ the righteous. He is the propitiation for our sins, and not for ours only but also for the sins of the whole world. And by this we know that we have come to know him, if we keep his commandments. Whoever says “I know him” but does not keep his commandments is a liar, and the truth is not in him, but whoever keeps his word, in him truly the love of God is perfected. By this we may be sure that we are in him: whoever says he abides in him ought to walk in the same way in which he walked.
These verses describe one of the classic Christian tensions, between our sinfulness and our goodness: Jesus’s followers do not sin; Jesus’s followers do sin. Now, empirically, we know that people who say they are Jesus’s follows do sin; are they therefore not his followers? Does Jesus have any true followers at all? On the one hand, we’re forced to say no: whoever says ‘I know him’ but does not keep his commandments is a liar, says John. On the other, it’s silly to say Jesus has no followers at all. How can we reconcile these positions?
One way is to take a gradualist position: we are (in the main, and over the long haul) getting better; we used to sin more than we do now, and we will sin less as our life (and our eternal life, especially) goes on. And this is certainly true.
But John shows an even better way: Jesus is not only our model for right behavior, he is our advocate, and “the propitiation for our sins, and not for ours only but also for the sins of the whole world.”
A friend of mine said over the weekend that when she is angry at someone for not living up to her standards, she has begun to think of this as being foolish and “a waste of the cross.” By this, I think she means that Jesus’s death and resurrection satisfies our need to become perfect (and, of course, to see others become perfect), and so her anger isn’t necessary: Jesus’s cross has already taken care of it. The cross of Jesus breaks the downward spiral of sin, self-condemnation, then even more self-condemnation. This is one of those things which is true even if we don’t realize it, but our lives will be easier and we will have more time and energy to expend on becoming who God wants us to be if we do. Let’s spend more time walking in the same way Jesus walked, and less time judging ourselves and others.