The Lord gave Ezekiel a message for the prophets who were devising messages for the Jews from their own hearts and calling them prophecies from Yahweh. He was using the word "prophet" ironically; these were not true prophets, but they claimed to be such. Ezekiel was to announce judgment on these false prophets. They were foolish (Heb. nabal) because they disregarded God"s word and relied on themselves. This is the essential mark of this type of fool in the Old Testament (cf1Samuel25; 2 Samuel 13:13; Psalm 14:1; Psalm 74:18). [source][source][source]
It is not clear in this chapter whether the Lord was speaking primarily of the false prophets in Jerusalem or in exile. Probably He meant false prophets in both places. [source][source][source]
"In the same way that impersonating a police officer is a crime in modern society, because it harmfully defrauds people who trust and obey the police, impersonating a true prophet of the Lord was, by God"s law, a fraudulent misleading of Israelites in Ezekiel"s day." [1][source]