Balaam's prophecy, "He shall not lie down until he eat of the prey, and drink the blood of the slain," was very quickly fulfilled. Shortly before his death, before he lay down to everlasting sleep, it was granted Moses to rejoice in the death of Balaam and the five Midianite kings allied to him. Israel's sinful profanation at Shittim, occasioned by Balaam's wicked advice, sorely smote Moses' heart.
God had appointed Moses as lord of the angels, who through fire and cloud had to step aside to make room for him and let him pass, yea, at his appearance they rose from their seats to do him honor. As he had power over the angels, so too did he rule the sea, which he clove at will and then commanded to resume its former guise, and the treasures of hail, which he employed to sent hail over the Egyptians.
Now this man, who was sovereign over the angels and over the forces of nature, could only weep when Israel committed whoredom with the daughters of Moab and Midian. To comfort Moses, God now said: "As truly as thou livest, thou shalt not depart out of this world until thou shalt have avenged those who tempted Israel to sin. 'Avenge the children of Israel of the Midianites: afterward shalt thou be gathered unto thy people.'"
God at the same time reproached Moses for his despair and lack of energy at Shittim, saying: "When all the tribes of Israel, save the tribe of Levi, were against thee, thou didst not then lack courage to stand up against all the people on account of the worship of the Golden Calf; how much more then at Shittim, when all Israel save only one tribe, the tribe of Simeon, were on thy side, shouldst thou have proven thyself sufficiently strong to keep back the sinners from their sin!"
When Moses received the command to wage war upon the people that had tempted Israel to sin, he said to God: "Yesterday didst Thou say to me, 'Vex not Moab,' and now Thou sayest, 'Avenge the children of Israel.'" God, however, replied: "When I said, 'Vex not Moab,' I named these people after their grandsire, the son of Lot, but not that through their own fault they have lost the claim to kind treatment from Israel, I shall no longer think of their grandsire Abraham's kinsman, but shall call them Midianim, 'they that lost their claim.'"