Banu Howazin was a tribe which inhabited the Turbah valley at two days march from Mecca. The tribe had indulged in some hostile activities against Islam, and in 629 A.D., the Holy Prophet decided to take punitive action against the tribe.
The Holy Prophet commissioned Umar to lead the expedition against Banu Howazin. The instructions of the Holy Prophet were that the tribe should be called to Islam, and in the event of their refusal, force should be used against them, and they should be driven away from the Turbah valley.
The Muslim expeditionary force consisted of thirty men. They had with them a guide of the Banu Hilal, who showed them the way, and led them to Turbah valley through unfrequented paths.
When the Muslim force reached the Turbah valley, they found that on hearing the approach of the Muslim force, the Banu Howazin had evacuated the valley and fled elsewhere with their animals and other belongings. The Muslim force stayed in the valley for some days. Scouts were sent in various directions to find some clue of the whereabouts of the Banu Howazin. No clue was found, and as the object of driving away the hostile tribe from the neighbourhood of Mecca had been achieved without firing a shot, the Muslim force decided to return to Madina.
When on the return march, the Muslim force reached ZiAljaza, about six miles from Madina, the Banu Hilal guide said:
As on the expedition against Banu Howazin you have had no booty, and if you want to return to Madina carrying some booty I can guide you against some other tribe Banu Kbusham have been afflicted with famine. I have seen them going that way. If you think of attacking them and getting some booty, I can take you by a path to such a place from where you could launch a surprise attack on them. In spite of famine conditions they have ample wealth with them which you could appropriate."
Thereupon Umar said:"The Holy Prophet merely sent us against Banu Howazin, and the object was to promote the cause of Islam and not to get booty for ourselves. As the Holy Prophet did not authorise me to attack any other tribe, I am afraid I can not attack any other tribe just for the sake of booty, without the express instructions of the Holy Prophet. "When on return to Madloa, Umar submitted his report to the Holy Prophet, and stated how he had not accepted the advice of the guide to attack Banu Khusham, the Holy Prophet said, "Umar you did well. If you had attacked them, I would have been unhappy."