“A lot of people don’t understand Jesus is a Jew but he’s the central part of Christianity. I have a hard time explaining it.”
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Simply put, Jesus is the Messiah that Jews had hundreds of prophecies about in the Old Testament. Jews WANT a Messiah, but they don’t believe that Jesus is The One. Why, I don’t know.
The Old Testament, and Judaism, is all about The Law (The Ten Commandments, the first five books of The Bible, etc.). God’s plan is that we cannot get to heaven by works, or by staying true to The Law. It is impossible for humans to remain sinless. So He gave us Jesus, who atoned for all of our sins in God’s eyes, by dying on the cross. Jesus paid the penalty and atoned for all our sins.
Jesus' existence was a threat to the religious institution in Jerusalem. They didn't want to lose their influence, power and control and that was what the presence of Jesus did.
The temple, the priests and their necessity was threatened and they eliminated the threat that was Jesus before they lost all they held dear.
JMO, YMMV
Simply put, in today's language, the religious leaders set the narrative and they silenced or eliminated anyone who went against it. Saul is a perfect example. Saul was on his way to Damascus to arrest Christians who would probably, eventually, be killed.
Force the belief that Jesus wasn't the Messiah and the people will know no different after a time.
It was indoctrination.
Again, JMO, YMMV
Since they are sinful from conception, no kidding.
Jesus fulfilled only about half of the messianic prophecies.
The ‘lamb’ prophecies refer to his roughly 3.5 years teaching
and preaching here on Earth, but the ‘lion’ prophecies refer
to His 2nd coming immediately before the millennial reign
where he conquers all of his enemies.