The answer is: A prophet of Judah

2 Kings 23:17-18 - The same prophet who made the prophecy hundreds of years earlier

When King Josiah was on his mission to restore the worship of Yahweh and to eradicate idolatry from Judah, his actions became iconic in the Biblical narrative. During his determined reforms, he came across the tomb at Bethel of a prophet from Judah who had prophesied against the idolatrous practices that Josiah was now fervently abolishing. Isn't it fascinating that this grave belonged to a prophet who lived several generations earlier? It adds a rich historical layer to the story!

The prophet’s prediction, which was made long before Josiah's time, ultimately guided Josiah's reform, showcasing how the distant echoes of God’s messages can reverberate through time and influence later events. The location of Bethel itself is significant — it was one of the pivotal sites of worship, known for its golden calf established by Jeroboam I. The decision of Josiah to leave this grave undisturbed shows remarkable respect and recognition toward the prophet’s mission and serves as a lesson of reverence for past truths.

It's also interesting to note that this moment reflects a broader theme in already established Biblical narratives where prophets play crucial roles in steering the course of Israel's history. Thus, we see prophecies paving the way for pivotal change and influencing leaders like Josiah in their quest for faithfulness in their time. Such connections challenge us to think about the legacy of wisdom left behind in historical narratives and how it continues to inspire those on a journey of genuine faith today.