God told me to... I would guess that most of us have interacted with someone who invoked God as a reason for what they do, or why we are to do something. As we see in Jeremiah and 2 Thessalonians, this claim to be speaking on behalf of God doesn't actually mean that they are.
Jeremiah is confronting a series of false prophets who told the people that comfort and peace would be theirs despite the fact that judgment and the Babylonian exile was what awaited. They communicated what the people wanted to hear and stamped it with God, to give it some force.
In the same way, Paul confronts those who believe that the "day of the Lord" has already happened. This message has come through "prophecy...word of mouth...by letter" but Paul says that in all of these cases they are wrong.
As we hear someone, whether a pastor, friend or stranger, claim to speak on behalf of God we must test it to see if it is true. If it doesn't match up with God's word then we should discard it as the lies that it is.
Question of the day: How can you test whether someone's claim to be speaking on behalf of God is valid?
Father God, thank you that you are a God who has spoken. You have spoken through your own voice, through the prophets, apostles and most clearly through your Son. Thank you that we have your word in the Bible and that you continue to speak through your Spirit. Give me a discerning heart to know what is from you and what is not. Amen.