Nor Should the Believers all go forth together: if a contingent from every expedition remained behind, they could devote themselves to studies in religion, and admonish the people when they return to them, that thus they (may learn) to guard themselves ( against Evil). (Quran 9:122)

The verse cited above says that there must be a group of people in Muslim Ummah in each region and period which should have extensive knowledge of Shariah in order to help the community to move in the right direction. This group should be equipped with enough capabilities to meet the challenges arising out of socio-economic and political developments.