This pericope is a piece of narrative written by St. Matthew. The main idea of this section is the importance of Christ’s impending death and it functions to bring the audience to repentance. Here, Jesus explains that He will himself be crucified and that following Him meant His disciples would acknowledge their own fallen state and accept the death they deserved. He declares that nothing on earth is worth as much as the life found in Him, and that He would return in might to reward the faithful.
Being a child of God means that He kills you and then raises you up.
That the hearers may be comforted in the struggles of their christian lives and have hope in the resurrection.
Our problem is the same as Peter’s: we find hope and comfort in the created thing of this life instead of in Christ.
Jesus died so that we might never taste death, and the Father raised Him up to show us what He does for His children.