The World Federation One Stop Fiqh

Ruling 780

If some clothing covers one’s private parts while he is standing but it is possible that it would not cover them in other positions – for example, in the position of rukūʿ and sujūd (prostrating) – then, in the event that when his private parts are visible he covers them by some means, his prayer is valid. However, the recommended precaution is that he should not perform prayers with such clothing.