"The Prophets," Not From God?

[Wrangler]

In this morning's Devotional Reading, I was struck in in 1 Kings 22. In verses 13, 16 "the prophets" are referenced but it turns out these prophets are not from God. This is in contrast with the NT references to "the law and the prophets" who are from God. Other than context, is there an explanation for the definite article to refer to different groups?

 

[Matthias]

Wouldn’t you agree that Jesus of Nazareth is identified in scripture? In fact, the prophet whom God promised to raise up from among the people in Deuteronomy 18:15,18?

The Messiah himself is a prophet -> not very controversial.

God himself is a prophet -> seems to fly in the face of what a prophet is.