I'm still slowly reading Packer's In My Place Condemned He Stood and I recently came across a section which I think speaks well to an unfortunate error that is often made by people trying to grasp what happened when Jesus died. Instead of writing a big intro I'm just going to quote Packer and then leave you with a quote from John Owen which I think also goes well with with this passage. Packer writes:
It was not man, to whom God was hostile, who took the initiative to make God friendly, nor was it Jesus Christ, the eternal Son, who took the initiative to turn his Father's wrath against us into love. The idea that the kind Son changed the mind of his unkind Father by offering himself in place of sinful man is no part of the gospel message - it is a sub-Christian, indeed an anti-Christian, idea, for it denies the unity of will in the Father and the Son and so in reality falls back into polytheism, asking us to believe in two different gods.
Packer then quotes John Murray writing:
The doctrine of the propitiation is precisely this: that God loved the objects of His wrath so much that He gave His own Son to the end that He by His blood should make provision for the removal of His wrath. It was Christ's so to deal with the wrath that the loved would no longer be the objects of wrath, and love would achieve its aim of making the children of wrath the children of God's good pleasure.
Here's John Owen on the Father's love: