The faith of the rich young man, so grounded in the teachings of the Pharisees and in the following of the law, was not really a "problem," except insomuch as it was a problem for the man himself. In following his faith to the letter, he condemned only himself.
When he walked away sad from Jesus, Jesus hung and shook His head, for the man's faith would not permit him to come out of his own box and follow Jesus. The man had signed his own seal, his own death warrant.
The sin of the Pharisees is greater because it was their sin that condemned the man, as well. They're the ones who had convinced him that this was the true faith, that this was what God had desired from him. The man himself had not condemned anyone else by his boasting, but the Pharisees had condemned the man by their teachings.
That is why when Jesus encounters the Pharisees, He does not shake His head; He shakes His fist. He raises His voice. He condemns them out loud, for they have condemned so many.
The same dynamic remains at work today.
There is none among us who can say that we have it all right, that we know exactly how it is that God desires for us to live, that we understand perfectly every word of His revelation. There is none among us who can say we live perfectly consistently, all the time, with all that we believe, let alone with all that God desires of us. And yet, there are some of us who try.
We have to be wise in discerning these situations, not just as outsiders, but as insiders - as those who are getting it wrong despite our desperate attempts to get it right. On one hand, we absolutely have to teach others about Christ. We have to tell them what it means to live by faith. We have to pass on His story so that it continues to grow and develop and reveal Him in this world.
But we have to be careful about how we do this. What we don't want to do is indoctrinate others into our own particular brand of Christianity, into the exact set of beliefs that we hold. We can't set them up for the same sins that we are committing, the same errors, the same slants. We have to pass on the faith in a way that, should we come to Christ and ask how we're doing, our shortcomings would condemn only ourselves.
We have to minister in such a way that God shakes His head, not His fists.
It's a difficult line to walk, particularly in light of the arrogance of our flesh that only lives the way that it lives because it is convinced that it is right. If we weren't convinced that we were right, we wouldn't be living this way. That wouldn't make any sense.
Yet we remain fallen, finite. We remain limited in vision and in insight. Even the best among us remains the least of these, and that ought to thickly paint our witness with humility. We ought at every turn to remind ourselves, and those who come after us, that we may not have it quite as right as we think we do, lest we condemn them by our teaching.
We ought at every turn focus our eyes on Jesus and declare, "I don't know if this is the way, but this is the Lord."