‏الفضائل : Hadeeth No:5766 'Ubida b. Samit reported that when wahi (inspiration) descended upon Allaah's Messenger (sallAllaahu alayhi wa sallam), he felt a burden on that account and the colour of his face underwent a change....

‏الجهاد والسير‏ : Hadeeth No:4469 It has been narrated on the authority of Salama who said: I joined seven military expeditions led by the Messenger of Allaah himself (sallAllaahu alayhi wa sallam), and nine expeditions which he sent out once under Abu Bakr and once under Usama b. Zaid....