Hypocrisy

hypocrisy/hɪˈpɒkrɪsi/
noun: hypocrisy; plural noun: hypocrisies

1. a pretense of having a virtuous character, moral or religious beliefs or principles, etc., that one does not really possess.
2. a pretense of having some desirable or publicly approved attitude.
3. an act or instance of hypocrisy.

The evangelist Billy Graham is quoted as inviting converts to join a church despite there being lots of hypocrites there. He told them that one more wouldn't make a difference.

The truth is that there are many people who call themselves Christians and/or are church goers but their claim to having a virtuous character and moral, religious beliefs and principles are in sad contrast with their actions and, usually, their words. They are justly labelled as hypocrites.

These people are not only an embarrassment to their proclaimed faith and fellow believers but to Jesus Christ himself. He gave a warning to his followers about this.

A good man brings good things out of the good stored up in his heart, and an evil man brings evil things out of the evil stored up in his heart. For the mouth speaks what the heart is full of. ‘Why do you call me, “Lord, Lord,” and do not do what I say? (Luke 6:45-46)
and...
‘Not everyone who says to me, “Lord, Lord,” will enter the kingdom of heaven, but only the one who does the will of my Father who is in heaven. (Matthew 7:21)