As Paul says, even though we as human beings know God, we refuse to acknowledge him. That's what Peter did. He refused even to "know" Jesus! Peter's failure reflects all our failure. It forces us to face the reality about ourselves. But the point of the story is that Jesus foretold this - he knew it was coming. And Jesus forgave Peter, when Peter confessed his love for Jesus. So the story illustrates both the horrible nature of sin, and the amazing reality of grace. That's essential to the whole meaning of the gospel.

God has made us humans in God's own image. So therefore the highest way to talk about God is by some kind of analogy with ourselves. So, naturally, if we who are finite and sinful suffer in multiple ways because of sin and evil and the horrible things that happen in our world, how much more does God, who is infinite, sinless, and knows the totality of all that happens to everybody, suffer pain and heartache at the suffering of his human and non-human creation - and be angry at all that causes it?

The Jews believed they were the nation God had chosen among all the nations. And they were. But that did not give them immunity to God's judgment. Like the nations, they too would feel God's wrath if they refused to live in God's ways. Furthermore, God could deal with other nations in mercy as well as judgment. Jeremiah was full of surprises, as against the popular religious assumptions of his day. That's perhaps why some people, when they encountered Jesus, thought he was very like Jeremiah. He turned things upside down.

Only the gospel exposes the cancer of idolatry.

Mission means inviting all the peoples of the earth to hear the music of God's future and dance to it today.

We may legitimately see in the [Old Testament] event, or in the record of it, additional levels of significance in the light of the end of the story – i.e. in the light of Christ

If "gospel" means good news, then Jeremiah had some for sure. He saw the judgment coming, in horrifying technicolour. But he saw beyond it to the redeeming, restoring grace of God, and indeed he speaks of the "new covenant", which takes us to the heart of the gospel in Christ.