When he rebuked Peter, he only did it cause Peter feared for him and yet, was standing in his way, wanting to save him. Jesus, however, had a big task he felt in his heart, had to do.
Take up the cross and follow, is mentioned in scripts, burden to bear, he knew his.
It was about intent.
We all have a burden to pick up, our purpose. We can all be thankful, to the one, and many, as there are many who have paved roads. This is one of them. He had to let his person die, so others could be free. Thats what he felt in his heart to do.
The calling Peter satan, telling him to get behind, was of course, im sure he'd love those who love him to talk him outa his fate, but he took that 'road' he knew where it would lead, but it was a road for others, so they could have everlasting life. And he gets really zen, 'whosoever will lose his life, shall find it...'
Matthew 8:
Jesus Predicts His Death
31He then began to teach them that the Son of Man must suffer many things and be rejected by the elders, chief priests and teachers of the law, and that he must be killed and after three days rise again. 32He spoke plainly about this, and Peter took him aside and began to rebuke him.
33But when Jesus turned and looked at his disciples, he rebuked Peter. "Get behind me, Satan!" he said. "You do not have in mind the things of God, but the things of men."
34Then he called the crowd to him along with his disciples and said: "If anyone would come after me, he must deny himself and take up his cross and follow me. 35For whoever wants to save his life[a] will lose it, but whoever loses his life for me and for the gospel will save it. 36What good is it for a man to gain the whole world, yet forfeit his soul? 37Or what can a man give in exchange for his soul? 38If anyone is ashamed of me and my words in this adulterous and sinful generation, the Son of Man will be ashamed of him when he comes in his Father's glory with the holy angels."