This is a perfect example of stupidity right here.
The sentence "I'll kill my son to forgive my children." and calling it irrational, which you did through various vibes.

Does more then one thing wrong.
For starters - it's simplifying something complicated. It's not meant to be done. I'll kill my SON

SON- Let us examine this for a moment. This would happen to be the scapegoat of our kind. Should you venture more then 3 pages in the bible, perhaps you'll learn that back in the day a priest would offer a goat - kill it as sacrifice that God would forgive His people. So with that out of the way - this isn't some big mystery - God is consistent.

Jesus was the ONLY perfect human being. He never sinned, never messed up. Ever - not once. NOT A SINGLE THING. NOTHING can be blamed on him. So God used him as the ULTIMATE SCAPEGOAT for us. That we all might be forgiven should we ask for it.

So shall we revise I, the Almighty God shall offer my One and Only Son - A perfect human being - as sacrifice so that the rest of my children may be washed in said blood and henceforth reborn and forgiven of their sins and transgressions. Yep - makes a lot of sense. It really, truly does.