“Get behind me, Satan, for you are not setting your mind on God’s interests, but man’s (Mark 8:33).”
I think the essence of what Jesus was saying is that Peter wanted a kingdom, not reconciliation of the lost.
God’s interests are sacrifice and reconciliation in the spirit. And in the eternal.
Man’s interests are glory, money, a kingdom here on earth. All temporal things.

This earth is passing away and is the tip of the iceberg. It’s what we see. And it’s temporal. But it’s held up by what is unseen. The unseen, which is eternal, is the foundation and reality that holds up this world, this iceberg tip.
If the unseen isn’t in right order, the tip will crumble and collapse and be washed away. If the seen isn’t in right order, but the unseen is, then the unseen can support the rebuilding and healing of the seen.
God’s interest is the unseen, the eternal. Man’s interest is the seen,the temporal.
“If anyone wishes to come after me, let him deny himself (let the tip of the iceberg fall away), and take up his cross, and follow me (Mark 8:34).”
“For whoever wishes to save his life shall lose it (the tip of the iceberg falls away); but whoever loses his life for My sake and the gospel’s shall save it…(Mark 8:35).” The foundation — the unseen — supports the rebirth and growth of new life.
“For what does it profit a man to gain the whole world (temporal), and forfeit his soul (eternal) (Mark 8:36)?”
I pray that my interests are the same as God’s. But, like Peter, one moment I’m there. Jesus is the Christ and I know it. All my interests are in Him. Then the next moment, all I can think about is my earthly kingdom and my earthly rights, my earthly hopes and understandings. Then Jesus says, “Get behind me, Satan.” And my eyes are again on Him. He’s first. He my all. And my interests are eternal. They are God’s interests.