Is it authentic from you that you said that the one who lets his garment hang below the ankles has his prayer not accepted, even if he prays a hundred prayers?

The questioner : It has been transmitted and spread among people that you said: the one who lets his garment hang below the ankles has his prayer not accepted, even if he prays a hundred prayers. Is this correct, O Shaykh?

The Shaykh : There is scholarly disagreement on this, based on a fundamental principle: Does the prayer of one who prays in a garment that is forbidden for him become invalid, or does it not? Some scholars said that it becomes invalid, because they stipulated that the garment with which one covers his 'awrah (part of the body that must be covered) must be lawful, and this is forbidden.
Others said that it is valid, because this prohibition is not specific to prayer, since letting the garment hang below the ankles is forbidden in prayer and outside of prayer. So, when it is not specific to prayer, it does not invalidate it. This is the more correct opinion, unless the hadith is authentic that the one who lets his garment hang below the ankles must repeat the prayer. If it is authentic, then no one has a view after it.