The answer is: Killed by a lion

1 Ki 13

The story of the prophet from Judah in 1 Kings 13 is a fascinating and cautionary tale that reminds us to remain vigilant about receiving divine instructions. This unnamed prophet was initially directed by God to deliver a stern message to King Jeroboam but was told not to eat or drink or even return via the same route. Trapped between temptation and obligation, he was deceived by a prophet from Bethel who claimed to have received a new message—a textbook case of unreliable communication, even in prophetic terms!

Truancy from God's original instructions led the Judah prophet into dire peril. When he disobeyed, a lion emerged to fulfill the ominous prophecy spoken due to his betrayal. This wasn't an ordinary lion; it spiritually echoed back to the bold, fearless lion images often associated with God’s judgement throughout scripture (think Revelation and even about Jesus, termed the Lion of Judah!). It serves as a startling reminder that mischievous or misleading voices can too easily lead even the most ardent servants off course if they rely solely on secondary directions instead of the original mandate.

An engaging bit of trivia: in biblical literature, the lion is regarded both as a figure of strength and divine vengeance, illustrating the gravity of the prophet’s mistake. This story beautifully emphasizes the importance of staying true to the full counsel and purpose of God, regardless of what others claim they have heard or interpreted!