O YOU who have attained to faith! No men shall deride [other] men: it may well be that those [whom they deride] are better than themselves; and no women [shall deride other] women: it may well be that those [whom they deride] are better than themselves. And neither shall you defame one another, nor insult one another by [opprobrious] epithets: evil is all imputation of iniquity after [one has attained to] faith; and they who [become guilty thereof and] do not repent - it is they, they who are evildoers!
Al-Hujurat (The Dwellings) Verse 12
The Prophet said, "Faith (Belief) consists of more than sixty branches (i.e. parts). And Haya (This term "Haya" covers a large number of concepts which are to be taken together; amongst them are self respect, modesty, bashfulness, and scruple, etc.) is a part of faith."
Volume 1, Book 2, Number 8