Source: Aḥkām wa Masāʾil in the Light of the Qur'an and Hadith, Volume 2
However, if someone naturally feels aversion or fears infection from the leprous person, they may practice caution based on the Hadith:
"فِرَّ مِنَ الْمَجْذُومِ فِرَارَكَ مِنَ الْأَسَدِ"
(Bukhārī)
Translation: "Flee from the leper as you would flee from a lion."
Thus, if someone avoids close proximity or refrains from praying alongside a leprous individual out of fear of illness, there is no sin upon them.
✔ A leprous person cannot be legally barred from entering the mosque.
✔ Avoidance due to fear of illness is permitted and carries no sin.
◈ Ṣaḥīḥ al-Bukhārī, Ḥadīth No. 5707
❖ Question
Is it permissible to pray behind a person with leprosy? Can a leprous individual join the prayer and can they be prevented from entering the mosque?❖ Answer
Leprosy is a physical illness and not considered a Sharʿī defect. Therefore, the Imāmah (leading of prayer) by a leprous person is valid, and they may participate in congregational prayers. According to Islamic law, they cannot be forcibly barred from entering the mosque.However, if someone naturally feels aversion or fears infection from the leprous person, they may practice caution based on the Hadith:
"فِرَّ مِنَ الْمَجْذُومِ فِرَارَكَ مِنَ الْأَسَدِ"
(Bukhārī)
Translation: "Flee from the leper as you would flee from a lion."
Thus, if someone avoids close proximity or refrains from praying alongside a leprous individual out of fear of illness, there is no sin upon them.
❖ Summary
✔ It is permissible to pray behind a leprous person, and their Imāmah is valid.✔ A leprous person cannot be legally barred from entering the mosque.
✔ Avoidance due to fear of illness is permitted and carries no sin.
❖ References
◈ Fatāwā Thanāʾiyyah, Volume 1, Page 265◈ Ṣaḥīḥ al-Bukhārī, Ḥadīth No. 5707
