As an individual, you should strive to always follow your moral code.

As a member of a group, you should accept that everyone is fallible — including and especially yourself and your ability to even define what constitutes fallibility.

There is much to lose and little to gain by ostracizing others for their immaterial human failings.

As with faith, sin also comes in many forms, from a semiotics perspective. But, one is probably best of not getting into too much detail as it can interfere with living one's best life (of which high self-esteem is a crucial component).

Just two obvious thoughts that may be relevant in this case.