an unqualified sense during the lifetime of the Messenger of Allah (1)—may Allah bless him and grant him peace—even though at that time he was his appointed successor [for leading the prayer] (2). It is thus [certainly] (3) established that the succession denoted by that title (4) was distinct from his succession in leading the prayer.
The second is that every person whom the Messenger of Allah—may Allah bless him and grant him peace—appointed to act in his stead during his lifetime—such as Alī during the Tabūk campaign, Ibn Umm Maktūm during the Trench campaign, Uthmān ibn Affān during the Dhāt al-Riqā campaign, and all the others whom he appointed over the territories of Yemen, Bahrain, al-Tāʾif, and elsewhere—was never entitled, without disagreement from any member of the Muslim community (5), to be called the Successor of the Messenger of Allah [may Allah bless him and grant him peace] (6). It is therefore established with inescapable certainty that this was the succession (7) over his community after him.
It is impossible (8) that they should have reached consensus on this if he (9) had not explicitly appointed him as his successor. If there were nothing here (10) except his appointment to lead the prayer (11), Abū Bakr would not (12) have had any greater claim to this designation (13) than the others we have mentioned (14).”