There are many things that are 4. 4 great things that are 4.
4 great ambiyaa, 4 great books, 4 sources of Shariat, 4 great angels. Why is it we have 4 seasons wihlst there is one sun ?
Why do we have 4 directions, 4 basic contents in our body. 4 major organs in our body, 4 Khalifs, allowed to marry 4 wives at one time, 4 major elements, etc. Why do we have 7 major Qiraats whilst we have one Quraan ? Every action of Nabi Muhammad (S.A.W) is beloved in the eyes of Allaah. All his noble actions, traits have been preserved within one or other Mazhab and even the pleasure of Allaah.