Imam shafi explaining the meaning of prophet commanding us to follow his tradition

Imam Shaf’i said:

“The Messenger of Allah (SalAllahu Alayhi Wasallam) telling his Ummah to hear his ahadith, to memorise them and then to propagate is evidence that this is the thing he ordered to propagate by which proof against an individual can be established that dawah was given to him. This is because the dawah can only be given based that which established to be halal from the messenger of Allah, that which is to be abstained from, actions that require legal punishment, affairs of this world and the hereafter…”

(ar-Risalah (pg.402-403) of Imam Shaf’i)