Verse of ikmal al-din

The verse of ikmal al-din (Arabic: إِکْمَال الدِّيْن) or the verse of ikmal refers to verse 5:3 of the Qur'an, the central religious text in Islam. Included in this verse is the passage,

ٱلْيَوْمَ يَئِسَ ٱلَّذِينَ كَفَرُوا۟ مِن دِينِكُمْ فَلَا تَخْشَوْهُمْ وَٱخْشَوْنِ ۚ ٱلْيَوْمَ أَكْمَلْتُ لَكُمْ دِينَكُمْ وَأَتْمَمْتُ عَلَيْكُمْ نِعْمَتِى وَرَضِيتُ لَكُمُ ٱلْإِسْلَـٰمَ دِينًۭا ۚ
This day those who disbelieve have despaired of your religion. So fear them not, but fear Me! This day I have perfected for you your religion, and completed My blessing upon you, and have approved for you as religion, submission [to God] (islam).

The interpretation of the verse of ikmal is disputed. Sunni sources offer different views, chief among them is that this verse was revealed to the Islamic prophet Muhammad during his Farewell Pilgrimage to Mecca to signal the completion of Islamic legislation, although some injunctions about riba were likely revealed later. By contrast, Shia authorities are nearly unanimous that the verse of ikmal was revealed following the announcement of Muhammad about Ali at the Ghadir Khumm, after his Farewell Pilgrimage and shortly before his death in 632 CE. In Shia sources, Muhammad received this revelation following his designation of 'Ali ibn Abi Talib at Ghadir Khumm to lead the nascent Muslim community after him. Some Sunni sources also associate the verse of ikmal with the Ghadir Khumm but reject its Shia significance.