How can a man be judged to be a committed Muslim, possessing good character and kindness, while wearing a chain around his neck, even though he prays?

The Muslim should exert his utmost effort in guiding people and strengthening their faith, and not occupy his time with judging them. We have been commanded to invite them [to Islam], advise them, and cooperate with them in righteousness and piety, following the example of the Companions who dealt with people according to what was apparent of their state of faith. So, whoever prays and faces our Qibla and eats our slaughtered meat is a Muslim. If there is a need to know the state of a person for a specific matter, there is no harm in that, provided his condition is concealed. It must be known that the occurrence of a mistake does not negate a person's good deeds, and the duty is to advise the one who errs while acknowledging his virtues.