Is a man married to four women, who divorced one of them, permitted to marry a fifth immediately after the divorce, or must he wait for the 'iddah (waiting period) of his divorced wife to end?

If a man divorces his wife with a revocable divorce, and he has four wives, he is not permitted to marry a fourth until the divorced wife's waiting period (iddah) expires. However, if the divorce is irrevocable (such as an outright pronouncement, or before consummation, or a khul'), he is permitted to marry immediately according to the Shafi'i and Maliki schools.

The Hanbalis and the People of Opinion (Ahl al-Ra'y) hold that there is no difference between a revocable and an irrevocable divorce; he is forbidden from marrying a fourth until the divorced wife's waiting period expires in all circumstances.