Shaikh Abdul-Muhsin al-‘Abbad hafidhuhallah was asked:
Question: Is the Hadith of Sahal ibn Sa’d mentioned recently evidence that the awrah being uncovered from below does not harm the one praying?
Answer: “A person should cover his awrah to the best of his ability and if it uncovers unintended due to the restricted situation then it does not have an affect. This is what happened in the Hadith of Amr ibn Salamah al-Jurmi radiallahu anahu who led the people in prayer. He had an izar which had a split, so something of his awrah was uncovered. So the woman said:
غطوا عنا عورة إمامكم
Cover the awrah of your Imam from us
[Bukhari no. 4302]
So they bought a Qamis for him and he was pleased and happy”.
[Sharh Sunan Abi Dawood no. 84]
Shaikh Salih al-Fawzaan hafiduhallah said:
Question: What is ruling on the one who prays and some of his awrah is exposed and he does not know until the end of the prayer, such that one of the congregants informs him of that. So is his prayer correct or does he have to repeat the prayer?
Answer: “There is no doubt that covering the awrah is from the conditions of the prayer along with the pillars. Ibn Abdul Barr rahimahullah said: “The People of Knowledge have agreed upon the invalidity of the prayer of one who prays naked and he is capable wearing clothes” or something similar. So covering the awrah is from the conditions of the validity of the prayer if he is able. As for what is mentioned in the question from this congregant praying and some of his awrah is uncovered and he did not know that until after the prayer and those who are attended the prayer informed him, then there is some detail:
If this one has a lot uncovered then he has to repeat the prayer. As for if it is something small and he did not intend it deliberately, then his prayer is correct in sha Allah. The evidence is that Amr ibn Salamah radiallahu anhu prayed with his Companions and he was young in age. If he used to make sujud, something of his awrah was exposed and the women would see it from behind the row. He did not repeat the prayer and that was in the time of the Prophet sallalahu alayhi wa salam. So that indicates that if something is uncovered of the awrah and it is a little and he did not intend it, then his prayer is correct. As for if he intended and left it off and did not cover his awrah and he was capable, then his prayer is invalid, even if it was a little”
[Muntaqa min Fatawa Shaikh Salih al-Fawzan no. 107]
Faisal Ibn Abdul Qaadir Ibn Hassan