´It was narrated that 'Abdullah said:` "The Sunnah divorce is to divorce her when she is pure (not menstruating) without having had intercourse with her."
Hadith Referenceسنن نسائي / كتاب الطلاق / 3424
Hadith Gradingالألبانی:صحيح | زبیر علی زئی:ضعيف، .3424] إسناد ضعيف، ابن ماجه (2020،2021) أبو إسحاق عنعن. انوار الصحيفه، صفحه نمبر 347
Hadith Takhrij«انظر حدیث رقم: 3423 (صحیح)»
Brief Explanation
1؎: The meaning of Sunni divorce is not that the act of the one giving divorce is Sunnah (prescribed by the Prophet) and meritorious, but rather its meaning is that for a person who is in need of giving divorce, the permissible and lawful method that has been mentioned in the Sunnah is that divorce should be given in such a period of purity (tuhr) in which the husband has not had intercourse with his wife.