In no way are we more mistaken about God than in our attitudes toward sin. We assume that God shares our concerns about perfectionism and moral rectitude. In our pride we think that our ethical standards, whether we apply them mercilessly to ourselves or to others, reflect God's own heart. In nothing are we farther from the example of Jesus.
I had a conversation a few months ago with a man who told me that Jesus' words about the log in your own eye and the speck in your brother's eye meant that first, yes, we should deal with our own sin -- but then we are expected, even commanded, to judge our brother and point out his sin. I was flabbergasted. How could a reasonable person read these verses and come to the conclusion that we are commanded to judge others? The answer, of course, is that we are not -- none of us -- reasonable people. We come with our own preconceptions and assumptions shaping our reading of the text. How can we get through all that to hear Jesus for what he is really saying? This requires the careful work of God's Spirit over time, to expose and strip away the colored glasses that so tint our perceptions. Our bedrock assumptions are hardest of all to see, and so often our bedrock assumption is that we do bad things and that God is angry because we do bad things. This childish understanding of morality has never been exposed to the light, and so we never come to realize the good news of Jesus. The good news is that we have been completely mistaken about God's attitude toward us. Jesus repeatedly speaks and models that God is mercy and kindness and love. The people whose sin Jesus railed against -- and he did -- were those who a) claimed to speak for God, and b) ruthlessly condemned those who did not meet their standard of moral behavior.
The problem with sinful behavior is that it puts up a barrier to a loving relationship with God. The problem with an ungodly focus on sin is that it puts up a barrier to a loving relationship with God.
I'm always amazed when Christians read texts like this what we hear Jesus saying. When Jesus says, "A disciple is not above his teacher but everyone when he is fully trained will be like his teacher," what picture comes to your mind? More often than not we will immediately focus on Jesus' moral perfection, on his sinlessness, on his absolutely seamless relationship with his Father, etc. But if God has given you the gift of brokenness, it is possible to hear these words in a completely different way, here and throughout the gospels. In the margin of my Bible next to this verse is a note I wrote in one of the lowest periods of my life: "4/3/17 -- despised, rejected, acquainted w/ grief, one from whom men hide their faces, numbered with sinners, friend of tax collectors and prostitutes." This was Jesus' earthly reputation. What does it mean to be fully trained to be like this teacher?
Perhaps Jesus' words about the log and the speck are designed to teach us humility. Instead of striving for sinlessness in terms of ethical perfection, perhaps we need to learn to come to God fully aware of our own wretchedness but also fully aware of his open-armed love and mercy. Maybe we need to learn to extend that same open-armed love and mercy to those around us without first speaking condemnation over their sin. That's the way Jesus modeled the character of God. That's the measure (v. 38) he calls us to use.