Imam Malik's Muwatta, Chapter: Jihad

Yahya related to me from Malik from Yahya ibn Said that Muadh ibn Jabal said, "There are two military expeditions. There is one military expedition in which valuables are spent, the contributor is willing, the authorities are obeyed, and corruption is avoided. That military expedition is all good. There is a military expedition in which valuables are not spent, the contributor is not willing, the authorities are not obeyed, and corruption is not avoided. The one who fights in that military expedition does not return with reward."