Numbers 11:1 - Wesley's Explanatory Notes

Complained — Or, murmured, the occasion whereof seems to be their last three days journey in a vast howling wilderness, and thereupon the remembrance of their long abode in the wilderness, and the fear of many other tedious journeys, whereby they were like to be long delayed from coming to the land of milk and honey, which they thirsted after. The fire of the Lord — A fire sent from God in an extraordinary manner, possibly from the pillar of cloud and fire, or from heaven. The uttermost parts — Either because the sin began there among the mixed multitude, or in mercy to the people, whom he would rather awaken to repentance than destroy; and therefore he sent it into the skirts and not the midst of the camp.