Jesus said "
Do not think that I came to destroy the Law or the Prophets. I did not come to destroy but to fulfill.
For assuredly, I say to you, till heaven and earth pass away, one jot or one tittle will by no means pass from the law till all is fulfilled.
Whoever therefore breaks one of the least of these commandments, and teaches men so, shall be called least in the kingdom of heaven; but whoever does and teaches them, he shall be called great in the kingdom of heaven.”
— Matthew 5:17–19
So Jesus fulfilled the old testament prophecy but did not replace the laws. If you do not follow the laws then you are sinning against your god. Is one to argue that Non Israelites are not obligated to follow the laws handed down from god in the old testament? Or must they follow them or else they are committing sin? Perhaps only the ten commandments apply to those of non Hebrew lineage?
The god of the Bible gave many rules to his chosen people. However the creator of all was so powerless to save all of those that believed in him, that he could not save them from sin without sending himself down to live a sinless life to allow them into his kingdom. We are talking about the creator of everything. He was powerless to save them from sin without sacrificing himself to himself.
He himself had to live the perfect sinless life to save all of those that believed in him, because living a perfect sinless life was impossible. He is all knowing all powerful omnipresent, yet he could not forsee the first sin, or perhaps he planned for the down fall of Adam?
Maybe those that go to heaven are predestined to be saved by his perfect plan? Maybe those that do not believe are meant to burn in hell for all eternity. Why would a perfect being that loves all of his creations, plan for there to be sin. Was he powerless to stop the fall of man? Why did he require the blood sacrifice in the old testament? Perhaps he isn't truly the god of all creation, but and a made up construct of man to explain morality.
We can look at his chosen such as Sampson, a truly evil man according to the Bible. A liar a thief a murder. A man that gave into his attraction to a woman and lost his power do to a hair cut. The man's only request was to be allowed to murder his fellow human by pulling down a building upon those who he himself had wronged. Such a righteous warrior of a god that requires blood.
If you only follow the teaching of Christ, then most of the bible is completely irrelevant to you. Other wise you not only endorse the brutal nature of the old testament god, you yourself must follow it. This includes striking down those that are the enemies of the old testament god. This is a major problem with the Bible. Not only is it full of contradicting passages, the god of the old testament is incredibly brutal and unforgiving.
We are talking about the architect of our existence. This is the same god the Islamic faith follows. A god that issued arbitrary death to those that he himself made to condemn.
Jesus told his followers that he would return in their age, yet here we are over 2000 years later waiting for his return. Why did he make a promise that he would return in their age, yet stay silent on giving his word for thousands of years. Perhaps he is not real and was a creation of flawed men that didn't have the knowledge of the world they lived in. Perhaps a creation of men trying to understand their own existence and meaning in this world. A false creator with no power in this world.