What are the types of ṭalāq (sunnī/bidʿī, rajʿī/bāʾin)?
Ṭalāq al-Sunnah is the prescribed manner: a single revocable ṭalāq pronounced in a ṭuhr (period of purity) in which there has been no intercourse, then left to run through the ʿiddah. Ṭalāq al-Bidʿah is the blameworthy manner: pronouncing during ḥayḍ, or in a ṭuhr after intercourse, or three at once — sinful, though the schools differ on whether it counts (see below). By effect: rajʿī (revocable) — the husband may take her back within the ʿiddah without a new contract; bāʾin (irrevocable) — minor bāʾin requires a new contract to remarry, and major bāʾin (after a third ṭalāq) bars remarriage until she lawfully marries and is divorced by another (without contrivance).
This answer does not split the positions by school.
Evidence:Qurʾān (65:1), (2:229–230); Bukhārī 5251 & Muslim 1471 (Ibn ʿUmar — divorce in a ṭuhr).
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