"Christos" literally means "grease". This is why the name "Christopher" exists, which means "bearer of (holy) grease", as it would make no sense to use it as a name for a man to "bear" Christ.
The Pagan Greeks did not have holy grease.
The concept comes from the Jews and other Semitic people who used holy grease and oil. They would smear the stuff on someone's head and proclaim him "mashiach" which is where we get "messiah". Both the Greek "Christ" and the Jewish "Messiah" mean "grease", but the practice traces squarely back to the Middle East, not Greece.
The teachings of Jesus say nothing about him being God in human form. Jesus also says expressly that he came only for "the lost sheep of Israel", which did not mean non-Jews. It meant bastard Jews. However, Jesus did alter that message at one point, when a gentile woman compared herself to a dog, and asked if dogs can get the scraps leftover after their masters (Jews) receive the blessings, and Jesus said it would be okay, so long as the master eats first.
As for sacrificing himself, this is properly understood by consulting Jewish beliefs. Moses in Exodus nailed a snake to a post, and when the Israelites gazed upon it, they were cured of their ailments and diseases. Jews also practice ritual slaughter with sheep, goats, and chickens. They believe that their sins are transferred onto the dying animal while they rub the animal's blood on themselves. Jesus was claiming that if he is sacrificed, the sins of the Jews will be wiped clean forever. That's why the Jews shout "may his blood be upon us and our children!"
To Europeans, that statement sounds like guilt, because of concepts like "blood on your hands". But for Semitic people, the blood represented the cleansing of your sins. That's why Pontius Pilate, a Roman character, wiped his sword and washed his hands, because it was not his beliefs.
So only the Jews in attendance were "saved". But then Saul of Tarsus wrote that if you are a gentile, you can participate in some redemption if you accept the Jew named Jesus as your god and renounce your pagan gods. This jives with Yahweh's OT commandement to the Jews to destroy the goyim's gods, break their idols, subvert their culture, and conquer their governments from within.
As for the teachings of Hillel, you don't have to take my word for it.
jewsforjesus.org/publications/issues/issues-v01-n02/the-talmud-and-the-gospels/
The House of HIllel had these teachings since the Second Century BCE. Jesus was just a character to give voice to them (along with having a basis of some actually Jews named Jesus who did things like lead a revolt of zealots or refused to pay taxes to Rome). And yes, the Sixth Century Talmud does say Jesus is boiling in excrement. This was Jews trying to undermine the Jesus cult and insulate themselves during their diaspora. If anything, Paul would agree with them… but you goyim can still get some "Jewish blessings" if you love Jewsus!