God is a Mass Murderer

[Belacqua]

time and time again jesus clearly states that the old laws are not to change, and that he has come to uphold these laws. 

That's true. And then he seems to change some of them. So it's not black and white. As you point out, the Bible seems to contain contradictions. 

It also depends on what we interpret the Old Testament stories to mean. Did Jesus take the genocides to be literal or figurative? Interpretations have varied. Paul gives examples of interpreting Old Testament history figuratively.

Let's just assume jesus existed for argument's sake.
he was the one who introduced the concept of a hell

I think you would have a difficult time proving this. Experts who read Hebrew and Greek and know the contemporary literature better than you or I disagree on this point. 

Early church fathers also disagreed. Origen, for example, thought that no one would spend eternity in hell. Consensus seems to have been reached officially around the year 400. But there are substantial minority traditions which disagree. Some Christians continued to believe that while the fires of hell are everlasting, the punishment there couldn't be. 

Much of the debate centers on some ambiguous Greek. Lewis Carroll, and others of his time, devoted many pages to philology attempting to prove that punishment could not be eternal. More recently a well-known scholar, who reads and translates from the originals, and teaches at Notre Dame, has published a book arguing that the original sources do not point to such punishment. 

So your confident statement here about Jesus and hell is certainly the view of some Christians, but not all of them. 

the idea that there’s a set of rules (immoral ones) that one must not break, and if you break these, no matter how trivial, nonsensical or absurd they may be; with ‘not loving him’ being the number one crime, you will be punished and tormented for eternity. it’s morally abominable.

You overstate the case. 

First, not all the rules are immoral. There are 613 of them, and some of them are just common sense. Others are just performative. Others are not things that modern people can agree with. Times change. 

The Jews knew that keeping all the rules all the time would be unreasonable, and had various ceremonies and rituals to make up for things. No one was expected to be perfect. They wrote a famous book about the only guy in history to have kept all of them. 

Christians say various things about the law. One of the big ones is that it is a stumbling block for the Jews, since it is impossible to keep. Jesus, they say, "fulfilled" the law by changing it from 613 detailed rules into one big one: love everyone as oneself. By following this one, they say you will do what is right without having to obey each of the OT prescriptions. It seems like a much more difficult rule to follow, since how we are to love everyone is ambiguous. A Christian would have to think for himself and work to obey one big difficult rule rather than the more detailed version.

However no Christian I'm aware of says that breaking one of these 613 is guaranteed to bring eternal damnation. Christians tend to be big on forgiveness, and even if a lot of them aren't as forgiving as we would like, that doesn't mean that the whole teaching is immoral. Just that they're not doing a good job. 

You're reducing the whole thing to something so simple it's really a caricature. Christianity is full of various ideas, to the point where almost nothing we can say about it is true of every Christian.