What is the ruling concerning a man who washes his right foot and puts his right sock on before he washes his left foot? Is it permissible for him to wipe over his socks?

Answer

Praise be to Allah.

You cannot wipe over your socks in this case, because you put the first sock on before completing the act of purification (wudoo’ or ghusl).

Source: Fataawa al-Lajnah al-Daa’imah, 5/247
