“When you speak all these words to them, they will not listen to you either; when you call to them, they will not answer you.” It's a cynical joke that there are some people whose purpose in life is to be a warning to the rest of us, but Jeremiah actually lived that out. The Israelites never listened to a single prophecy of his, and he knew that they never would. Not before the Babylonian Exile, and amazingly, not afterwards either. Other, false prophets were telling them what they wanted to hear. He had only persecution and failure to look forward to, yet in that failure, he was being faithful to God's call.
Sometimes that is the role of any Christian, up against a world that has much more pleasant things to think about than the Cross. “Whoever is not with me is against me,” and right now that means being with Christ in the desolation of the desert and the way to Golgotha.