Received order of excellence: Abū Bakr, ʿUmar, ʿUthmān, ʿAlī.
Historical order of succession: Abū Bakr, ʿUmar, ʿUthmān, ʿAlī.
The first concerns religious rank and overall merit, the second the establishment of communal leadership. Early differences in limited comparisons, especially between ʿUthmān and ʿAlī, do not erase the distinct history of consultation and allegiance through the four caliphates.
Sound theological study distinguishes the nature of a disagreement, the precise implication of the evidence, and the respect due to those whose views are discussed.