Why does Jeremiah refer to all the prophets who have spoken of war and say that the prophet who speaks of peace will be known as a true prophet when peace comes?

Having affirmed Hananiah’s message of restoration (Jeremiah 28:6), Jeremiah now calls on Hananiah and those listening to consider the pattern of prophecy in Israel’s history. He points out that there is a long line of prophets who prophesied a message of war, famine, and pestilence against many countries and great kingdoms. This is certainly true of Israel’s prophets, and it was true of Jeremiah. Prophets who preached peace, such as Hananiah, stood outside this long tradition and he could only be seen as a true prophet of the Lord if his prophecy came to pass. Jeremiah is applying the test of a true prophet that the Lord gave Israel in his covenant (Deuteronomy 18:21–22). Jeremiah’s reasoning here seems to be that his message of judgment is consistent with the line of prophets who had preached a similar message and whose prophecies had come to pass, whereas Hananiah’s message of peace was novel and untested. This is not to suggest that the Lord’s true prophets, including Jeremiah, never spoke of peace. They did, but the peace they spoke of only came after a time of judgment. Hananiah’s message did not include any judgment.  

It is impossible for those listening in the temple to apply the test of Deuteronomy 18:21–22 to Hananiah’s words. They would have to wait for two years to see if his prophecy came true. That would remove any opportunity to respond positively to Jeremiah’s message by submitting to the Babylonians who were on their doorstep. However, after Jeremiah’s prophecy did come true in 587 BC, those reading of this account in exile in Babylon would know that Hananiah’s prophecy did not come to pass. This would have been a powerful incentive for the exiles to turn to the Lord in repentance and trust in his promise of restoration after seventy years of exile had passed.

However, even though those listening to Jeremiah and Hananiah in the temple could not apply the test of Deuteronomy 18:21–22 to Hananiah’s message, what should have been clear to those who had ears to hear is that Hananiah’s message was not consistent with the covenant. The other measure of a true prophet in the covenant was whether they led the people in faithfulness to the Lord (Deuteronomy 13:2). Jeremiah’s sermon in Jeremiah 26:1–24 has made it very clear that the Lord’s judgment is coming to Judah because they have refused to walk in faithfulness to the Lord and his covenant (Jeremiah 26:4–6). Jeremiah understood that obedience and holiness were fundamental aspects of faithfulness to the Lord: Hananiah makes no mention at all of Judah’s unfaithfulness. The question asked by this narrative is, Which of the two prophets has “stood in the council of the LORD (see Jeremiah 23:18, Jeremiah 23:22)"? It cannot be both of them.¹ But for anyone with any sensitivity towards the Lord and his covenant it should have been clear that Jeremiah was the prophet calling the nation to repent of her unfaithfulness and return to the Lord.