Much of the Old Testament is not from God - it is stuff either added by the Priests to protect their power, the kings to protect their power or the kabballah witches to protect their power.
It was accepted in the ancient Jewish world that there were two sides to the Bible - two threads that braided together but were not the same.
This way of telling myths was paradoxical - it operated on two levels that were not resolvable and yet coexisted.
That's why the Bible contradicts itself all over the place.
For the Magliens this represented their alien logic - two things that were contradictory could be true. For them A = A = B. For us A = A means that A cannot = B. For the Magliens an Apple can be both an Apple and an Orange. They can't
process simple logic like we can.
The early followers of God allowed this corruption because they believed that God's message would rise to the top. The cream would rise.
Similiar to how the Founding Fathers believed that free speech would allow the best ideas to rise to the top and thus there was no reason to censor bad or evil ideas like racism and slavery, the early followers of God thought that
by allowing the devil's story (magliens story) to be braided into God's story they could allow both to co-exist and avoid war between them and eventually God's story would win. The believers in God's message knew that ultimately humans would be able to
sort out the lies from the Truth and God's story would rise.
People do this naturally actually. Few people remember anything from the Bible where it lays out prohibitions against what you can't eat and the price for various things in shekels - like how much for a slave you mistakenly kill him.
People can't necessarily remember the commandments in order but they know killing people is evil and the Bible says so. Pretty much everyone gets the point of do unto others as you would have done to you. Altruism is actually our
natural condition - we have to learn to be selfish. Children naturally share with each other even when they're in situations of scarcity - even more so if they are actually.