The Book of Divorce
18/4. Chapter:
Giving one's wife the choice does not count as a divorce, unless it is intended as such
Sahih Muslim
وَحَدَّثَنَاهُ أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا عَلِيُّ بْنُ مُسْهِرٍ، عَنْ إِسْمَاعِيلَ بْنِ أَبِي، خَالِدٍ عَنِ الشَّعْبِيِّ، عَنْ مَسْرُوقٍ، قَالَ مَا أُبَالِي خَيَّرْتُ امْرَأَتِي وَاحِدَةً أَوْ مِائَةً أَوْ أَلْفًا بَعْدَ أَنْ تَخْتَارَنِي وَلَقَدْ سَأَلْتُ عَائِشَةَ فَقَالَتْ قَدْ خَيَّرَنَا رَسُولُ اللَّهِ صلى الله عليه وسلم أَفَكَانَ طَلاَقًا.
Masruq reported: I do not mind if I give option to my wife (to get divorce) once, hundred times, or thousand times after (knowing it) that she has chosen me (and would never seek divorce). I asked 'A'isha (Allah be pleased with her) (about it) and she said: Allah's Messenger (ﷺ) gave us the option, but did it imply divorce? (It was in fact not a divorce; it is effective when women actually avail themselves of it.)
Reference : Sahih Muslim 1477bIn-book reference : Book 18, Hadith 34USC-MSA web (English) reference : Book 9, Hadith 3501