I've been reading The Sealed Nectar by Safi Ur Rahman Al-Mubarakpuri and usually military expeditions would be dispatched for some treachery committed by a tribe or some other atrocities committed by them, but for this one the tribe of Bani Kalb, Abdur Rahman Bin Awf was sent on a military expedition towards them and my question is for what reason? It says that they were enemies of the Muslims but I couldn't recall reading about them so for what reason was the expedition called for?

