Why did God do Satan’s bidding?

[Angrboda]

Well, there are as many interpretations of the events in the story of Job as there are readers of it. A few things to keep in mind, though. First off, Job is a very strange book. It is unusual in content compared to the rest of the Judaic literature (alongside such other oddball greats as Ecclesiastes and Psalms). So it would be unwise to draw general conclusions from this somewhat atypical book. Second, the book of Job is by many considered to be one of the oldest stories in the Old Testament, and may not even have been Jewish or Hebrew in origin. Yet another reason not to cast your net too wide. Third, it must be borne in mind that in pre-Maccabees Judaism, Satan wasn't the powerful foe of God and tempter of men that he would later become in late Rabbinic and Christian thought. At the time, Satan's figure was basically that of an angel, essentially no different from any other angel. (Anyone who has studied the development of the concept of angels in Judaism and Christianity will recognize that angels, generally speaking, each had their own dominion, their own area of responsibility, tasked by God, for which they were uniquely suited. Apparently, at this time, Satan's job involved some meetin' and greetin' of the plain folk on Terra Firma.)

So what do we have after clearing away the most obvious debris? Not sure, but it's not important enough for me to be arsed to think about it any more deeply.