AP: As we can see from the brief overview we have provided in previous posts (see here, here, here, and here), the Jewish people were surrounded by religions that believed in demons or evil beings, but had not yet developed–except perhaps for Ahriman in the Iranian world–a concept of the devil as we understand it today. The Israelites also adopted some of those more or less common ways of thinking, but to them belongs the honor of giving shape over the centuries to the concept of the devil, which is very common in today's world that is heavily influenced by the Christian faith.
We now turn our attention to what the Jewish literature prior to Christianity say about the devil and demons. These ideas are the immediate antecedent of Christian ideas about the same subject. The Old Testament clearly distinguishes between an alleged evil spirit called Satan and demons, so we need to treat them separately in our discussion.
First, Satan hardly appears throughout the Old Testament, and the figure of an evil spirit (i.e., evil incarnate) is fuzzy. There are barely a dozen texts in which we find the word "Satan."
In the Hebrew Bible this word is not normally a proper name or the name of a particular spirit, but a common name, which means "adversary" or "enemy." It can be used in the most trivial sense of the term with some legal, military, or political connotations, the latter possibly serving as the origin of the term. As a common name, the designation of "Satan" can apply to both men and spirits.
We can see this, for example, in the familiar story of the prophet Balaam who was hired by Balak king of Moab to curse Israel. When Balaam was on his way to curse Israel "Yahweh was angry because he was going, and the angel of the Lord took his stand in the way as an adversary (literally, "satan") against him" (Num. 22:22a).
Similarly, David called one of his companions a "satan." I'm referring to Abishai, who suggested to the king that he should put Shimei to death. But David replied, "What have I to do with you, O sons of Zeruiah, that you should this day be an adversary (literally, "satan") to me?" (2 Sam. 19:22a).
Someone could use the term "satan" to refer to an opponent on the battlefield as well. Thus, in 1 Sam. 29:4, the lords of the Philistines refer to David in the following manner: "Make the man go back, that he may return to his place where you have assigned him, and do not let him go down to battle with us, or in the battle he may become an adversary (literally, "satan") to us."