In 1 Kings 22:19-22 it appears God is sending a spirit to tempt false prophets to lie. This would be contrary to James 1:13-14. I see this as similar to the discussion God has with Satan beginning in Job 1:6. The "host of heaven" in 1 Kings 22:19 could include Satan/demons. God is not tempting, but being all-knowing it was clear to him this would be an opportunity to deceive which the demons could not pass up. Is this explanation valid? Also, would it be accurate to say those on this his left (1 Kings 22:19) would be the demons? 

The short answer is that in the OT causes are often assigned to God, whether primary or secondary. That is, all events, positive or negative, are ascribed to the Lord. See, for example, the disaster sequence in Job. Or consider Jesus’ words, God sends his rain on the righteous and the unrighteous. What is permitted is often described as a direct action of the agent.

Modern people make a hard distinction between primary and secondary causation. But this is not how most people reasoned in biblical times. The task for us is to enter their world and appreciate their way of thinking.

As for demons, these are not equated with lying spirits or even unclean spirits, though this may well be the case. Have you listened to my podcast on Demon possession and exorcism?

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