To err is human. As long as this worldly life extends humankind will not stop making sins. But it is those who repent who are the best among humankind.

Though sincere repentance should deter a person from falling in the same sin once again, we find some repentant persons commit their old sins at times. This does not necessarily mean that their repentance was not a sincere one. The nature of human soul is generally complicated and volatile.

So, we are required to deal with people according to what appears to us from them. We cannot open their hearts to know their true intentions, though their outward deeds may manifest them. As long as a person shows regret and repentance and we trust their sincerity we should accept this from them and treat them accordingly.

At the same time, if a Muslim has a doubt regarding the straightforwardness and religiosity of a particular person, this lack of trust cannot be a basis of a good relationship.