In Mark 7, we find a familiar story: Jesus sits down to eat with some of his disciples, and the Pharisees complain because they have not washed their hands in keeping with the tradition of the elders. "Why do your disciples eat with defiled hands?" is the question they pose.
Jesus will have none of it, of course, and he rips into them rather hard:
Isaiah prophesied rightly about you hypocrites, as it is written,
'This people honors me with their lips,
but their hearts are far from me;
in vain do they worship me,
teaching human precepts as doctrines' (7.6-7).
Christ gives the specific example of Corban. A person could give a significant amount of money normally due to his parents as Corban, which means the parents would have no access to it, since it would be an offering to God. Jesus insists that this compromises the filial duty imposed by the Torah that children honor their parents and care for them.
More importantly than the specifics of this story, however, is the moral attitude that Jesus takes towards the Pharisees, and the way in which he addresses them. He doesn't give their objection to his disciples any attention until after he has had his time to polemicize. The lesson to learn: a moral objection from a hypocrite, especially an objection about a speck in the eye of another coming from a person with a log in his own eye, deserves little if no attention.
This is exactly the lesson many Christians ought to learn. I know some persons who have no problem objecting left and right to the mistakes of those around them. They don't even seem to realize that this hypercritical attitude is a worse failing than the ones they are busy blaming!
This is a lesson we can all agree on. Most people are quick to answer, "You're one to talk!" when an objection or criticism comes from a less than impressive source. In light of the reality of human sin, however, it is very likely that often we offer just such morally unimpressive objections and criticisms ourselves. Other people have no obligation whatsoever to listen to us or pay us any attention, if we cannot present ourselves as worthy sources of moral knowledge and input.
Better to keep quiet, do what is right, and offer advice on rarer occasions, when you have demonstrated your worthiness to the satisfaction of the recipients.