There cropped up a difference of opinion between a group of Muhajirs (Emigrants and a group of Ansar (Helpers) (and the point of dispute was) that the Ansar said: The bath (because of sexual intercourse) becomes obligatory only-when the semen spurts out or ejaculates. But the Muhajirs said: When a man has sexual intercourse (with the woman), a bath becomes obligatory (no matter whether or not there is seminal emission or ejaculation). Abu Musa said: Well, I satisfy you on this (issue). He (Abu Musa, the narrator) said: I got up (and went) to 'A'isha and sought her permission and it was granted, and I said to her: 0 Mother, or Mother of the Faithful, I want to ask you about a matter on which I feel shy. She said: Don't feel shy of asking me about a thing which you can ask your mother, who gave you birth, for I am too your mother. Upon this I said: What makes a bath obligatory for a person? She replied: You have come across one well informed! The Messenger of Allah ﷺ said: When anyone sits amidst four parts (of the woman) and the circumcised parts touch each other a bath becomes obligatory.  

اخْتَلَفَ فِي ذَلِكَ رَهْطٌ مِنَ الْمُهَاجِرِينَ وَالأَنْصَارِ فَقَالَ الأَنْصَارِيُّونَ لاَ يَجِبُ الْغُسْلُ إِلاَّ مِنَ الدَّفْقِ أَوْ مِنَ الْمَاءِ وَقَالَ الْمُهَاجِرُونَ بَلْ إِذَا خَالَطَ فَقَدْ وَجَبَ الْغُسْلُ قَالَ قَالَ أَبُو مُوسَى فَأَنَا أَشْفِيكُمْ مِنْ ذَلِكَ فَقُمْتُ فَاسْتَأْذَنْتُ عَلَى عَائِشَةَ فَأُذِنَ لِي فَقُلْتُ لَهَا يَا أُمَّاهْ أَوْ يَا أُمَّ الْمُؤْمِنِينَ إِنِّي أُرِيدُ أَنْ أَسْأَلَكِ عَنْ شَىْءٍ وَإِنِّي أَسْتَحْيِيكِ فَقَالَتْ لاَ تَسْتَحْيِي أَنْ تَسْأَلَنِي عَمَّا كُنْتَ سَائِلاً عَنْهُ أُمَّكَ الَّتِي وَلَدَتْكَ فَإِنَّمَا أَنَا أُمُّكَ قُلْتُ فَمَا يُوجِبُ الْغُسْلَ قَالَتْ عَلَى الْخَبِيرِ سَقَطْتَ قَالَ رَسُولُ اللَّهِ ﷺ إِذَا جَلَسَ بَيْنَ شُعَبِهَا الأَرْبَعِ وَمَسَّ الْخِتَانُ الْخِتَانَ فَقَدْ وَجَبَ الْغُسْلُ