"It is He who sent His Messenger with guidance and the religion of truth" (referring to) Islam, "to manifest it over all religion." Al-Hasan’s interpretation: So that it prevails over the religions. Ibn Abbas’s interpretation: So that the Prophet is made to prevail over all religions; meaning: over all the laws of religion. The Messenger of Allah (peace be upon him) was not taken by death until Allah had completed that.
Interpretation of Surah al-Fath, Verse 29.
﴿هُوَ الَّذِي أَرْسَلَ رَسُولَهُ بِالْهُدَى وَدين الْحق﴾ (ل ٣٣٢) الْإِسْلَام ﴿لِيُظْهِرَهُ عَلَى الدِّينِ كُلِّهِ﴾ تَفْسِير الْحسن: حَتَّى يحكم على الْأَدْيَان. وَتَفْسِير ابْن عَبَّاس: حَتَّى يظْهر النَّبِي على الدّين كُله؛ أَي: على شرائع الدّين كلهَا، فَلم يقبض رَسُول الله حَتَّى أتم الله ذَلِك.
تَفْسِير سُورَة الْفَتْح الْآيَة ٢٩.