And when a sūrah was revealed [enjoining them] to believe in Allāh and to fight with His Messenger, those of wealth among them asked your permission [to stay back] and said, "Leave us to be with them who sit [at home]."
When Allah reveals a sūrah to His Prophet (peace be upon him) that contains the instruction to have faith in Allah and to strive in His path, the rich people from among them ask you for permission to stay behind and they say: Let us stay behind with those who are excused, such as the weak and those who are chronically ill.