Jeremiah was a prophet of Judah. Jeremiah was probably only about twenty years old when the Lord informed him of his special calling to prophesy against Hiis people. At first Jeremiah was reluctant, but the Lord told him not to fear the people, for He would be with him (Jeremiah 1:17–19).
Jeremiah began his ministry in the days of the godly king Josiah, but he would eventually witness the destruction of Jerusalem and the temple at the hands of the Babylonians. All the while, he faithfully warned the people of the impending consequences of their wickedness and idolatry.
Jeremiah was often perceived as a traitor for preaching his messages of doom. Once some royal officials of Judah even put Jeremiah in an empty cistern until he was rescued by a Cushite named Ebed-Melech (Jeremiah 38). After the Babylonians attacked Jerusalem and destroyed the temple, some fleeing Judeans took Jeremiah with them to Egypt, where he prophesied more messages of doom and probably spent the rest of his life.
Have you ever faced a situation where you had to warn others about the consequences of their actions? Even if the people you are speaking to become angry or threaten you with harm, you do not need to fear—the Lord is with you, just as He was with Jeremiah.