Ghusl Absorbs Wudu

Ghusl is the greater purification and wuḍūʾ the lesser; once ghusl has been made, wuḍūʾ is not made again on top of it. It is like a house already fully painted throughout: one does not go back and ask whether a single room needs painting over again — the whole house is done. So long as the ghusl remains unbroken, prayer may be offered on its strength alone, and no further wuḍūʾ is required for it. Should the ghusl be broken afterwards, however — by passing wind, for instance — then wuḍūʾ becomes necessary again before ṣalāh, exactly as it would after any other event that breaks it.