وَإِنْ أَقْطَرَ فِي إِحْلِيلِهِ: لَمْ يُفْطِرْ عِنْدَ أَبِي حَنِيفَةَ وَمُحَمَّدٍ، وَقَالَ أَبُو يُوسُفَ: يُفْطِرُ.
Translation: If drops are instilled into the urethra, the fast is not invalidated according to Abu Hanifah and Muhammad, whereas Abu Yusuf holds that it is invalidated.
Iḥlīl denotes the urethra, the urinary passage. In this exact classical case, Abu Hanifah and Muhammad hold that instilling drops there does not invalidate fasting; Abu Yusuf holds that it does.
Avoid collapsing the two disciples into a single position in every issue: in this passage Muhammad agrees with Abu Hanifah, not with Abu Yusuf.