The reason for the prohibition of wearing trousers or a waist-cloth below the ankles
Question
Why is it forbidden to wear trousers or a waist-cloth below the ankles, whether in the state of prayer or in any other state?
Answer
It has come in the hadith that whoever covers the ankles (with trousers or a waist-cloth), that part will burn in Hell. Therefore it is makruh tahrimi, and likewise the prayer also becomes makruh tahrimi.
Source: Fatawa Mahmudiyya
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