Reference: Sharh ‘Umdatil-Fiqh – Tape No.4, Question No.11
Question: If someone was wearing socks, and wiped over them [whilst performing wudhoo], and later he took them off whilst being in the state of wudhoo – would it then be correct for him to pray [as he is]?
Response: No; his wudhoo has been invalidated because he has taken off his socks, and his feet have been exposed. So he is [now] required to [perform wudhoo anew, and] wash his feet, because [wearing socks justified him wiping over them when performing wudhoo, and now he has taken them off], his justification has expired.
