Sunan Abi Dawud, Hadith 3873

Judamat al-Asadiyyah said that she heard the Messenger of Allah (May peace be upon him) Say: I intended to prohibit suckling during pregnancy (ghailah), but I considered the Greeks and the Persians and saw that they practiced it, without any injury being caused to their children thereby. Malik said : Ghailah means that a man has intercourse with a women while she is suckling a child.

حَدَّثَنَا الْقَعْنَبِيُّ، عَنْ مَالِكٍ، عَنْ مُحَمَّدِ بْنِ عَبْدِ الرَّحْمَنِ بْنِ نَوْفَلٍ، أَخْبَرَنِي عُرْوَةُ بْنُ الزُّبَيْرِ، عَنْ عَائِشَةَ، زَوْجِ النَّبِيِّ صلى الله عليه وسلم عَنْ جُدَامَةَ الأَسَدِيَّةِ أَنَّهَا سَمِعَتْ رَسُولَ اللَّهِ صلى الله عليه وسلم يَقُولُ ‏ "‏ لَقَدْ هَمَمْتُ أَنْ أَنْهَى عَنِ الْغَيْلَةِ حَتَّى ذُكِّرْتُ أَنَّ الرُّومَ وَفَارِسَ يَفْعَلُونَ ذَلِكَ فَلاَ يَضُرُّ أَوْلاَدَهُمْ ‏" ‏ ‏.‏ قَالَ مَالِكٌ الْغَيْلَةُ أَنْ يَمَسَّ الرَّجُلُ امْرَأَتَهُ وَهِيَ تُرْضِعُ ‏.‏

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also referenced under: Hadith 3882 (DarusSalam)