What is our duty towards a man who claims to be a Muslim and resides in an Islamic country, but rarely attends the mosque, saying that he prays at home, while retaining Christian residency and passport, and claiming to possess a certificate proving his conversion to Islam?

A Muslim must outwardly demonstrate the rituals of Islam to the best of their ability, and be truthful in their claims by performing acts of worship. People are only judged by what is apparent from them, for the fundamental principle is that anyone who pronounces the two testimonies of faith is a Muslim, unless they commit an act that negates Islam. Abu Bakr (may Allah be pleased with him) fought those who withheld zakat, and the Prophet (peace be upon him) stated that he was not commanded to search into people's hearts. Umar ibn al-Khattab (may Allah be pleased with him) mentioned that they judge by what is apparent from people. Accordingly, one must believe anyone who outwardly displays Islam and prayer, even if rarely. Such a person should be honored, taught the rulings of the religion and the importance of prayer, and treated with good character, for they might be influenced and become sincere.