The Islamic ruling on performing prayer while sitting due to fatigue
Question:- If a man is tired and not physically capable to offer his prayers while standing, is he allowed to offer his prayers on chair or on floor?
Answer:- Since standing in prayer is one of the obligations of prayers, fatigue is not an excuse for which a person can be allowed to sit. Such a person should rest for a while before prayers and offer prayers reciting short surahs. However, non-obligatory prayers (Nawafil, Sunnah Mokidah Prayers etc.) can be offered while sitting without any reason.