What is the ruling regarding the waiting period ('iddah) if a man divorces his wife, or the marriage is nullified, and then remarries her during her 'iddah, and subsequently divorces her again?
General Chapter
Al-Mughni
Book of Reconciliation (Return During 'Iddah)
Primary text
If consummation ('dukhul) occurred in the first marriage, the wife must observe the 'iddah from the subsequent divorce without dispute, as it constitutes a divorce in a consummated marriage preceded only by that divorce. The basis for this is that the second marriage is validly contracted during the 'iddah following a consummated marriage, and the ruling of the first 'iddah remains applicable.
Supporting text
If no consummation occurred in the first marriage, the correct opinion within the established madhhab holds that she continues the remainder of the original 'iddah. A dissenting opinion, held by Abu Hanifa, suggests she must start a new 'iddah, arguing by analogy with the case of revocable divorce (raja'ah), where divorce after revocation requires restarting the 'iddah, which is a stronger bond than the current situation.