Sayyiduna Abu Mas’ud Ansari (may Allah be pleased with him) narrates: The Noble Prophet (peace and blessings be upon him) used to straighten our shoulders before the prayer began and would say:“Do not differ among yourselves (i.e., do not stand ahead or behind each other), otherwise your hearts will also differ. Let those among you who are wise and experienced stand closest to me, then those who are next to them in rank, then those who are next to them in rank.”