And according to the New Testament, Christians don't even follow the Mosaic Law anymore. (e.g. Circumcision is not required)
Did Jesus not say "every jot and tiddle" of the old law was to be obeyed? In any case, the mosaic laws do not speak well of your "perfect" god. He gave explicit directions on how men could sell their daughters into slavery, how much people could charge for slaves, how hard they were allowed to beat their slaves, how they were to mark them as property (by driving a stake through their ear), etc. Even the "kindler gentler" new testament never condemns slavery. On the contrary..
Slaves, obey your earthly masters with deep respect and fear. Serve them sincerely as you would serve Christ. - Ephesians 6:5
Christians who are slaves should give their masters full respect so that the name of God and his teaching will not be shamed. If your master is a Christian, that is no excuse for being disrespectful. You should work all the harder because you are helping another believer by your efforts. - 1 Timothy 6:1-2
That servant who knows his master's will and does not get ready or does not do what his master wants will be beaten with many blows. But the one who does not know and does things deserving punishment will be beaten with few blows. - Luke 12:47
For that you'll have to go back to the challenge presented in the Garden of Eden. By eating the forbidden fruit, humankind decided they can rule themselves without God.
Fail. This was the tree of KNOWLEDGE. Before they ate the fruit, they had no knowledge of right and wrong, good or evil. Without knowledge of the concept of evil, they had no means of knowing their actions were evil..yet they were punished anyway. Think about this buddy..God is timeless and omniscient, which means he knows everything that will ever happen. He created a man with an inquisitive nature (knowing how he would respond to the magic tree). He then proceeded to create the tree, create the evil talking snake, allow the snake into the garden, then allow the "crime" to take place. Unless God is flawed and possesses imperfect knowledge, he knew the millisecond he finished creating Adam that this would happen..yet he chose to do it anyway, rather than erasing him and starting over. It's just like dropping your cat/dog, then punishing it for hitting the ground.
If you want to cling the assumption that God is omniscient, the only conclusion you can draw from the Adam story is that "the fall" (and subsequent punishment of BILLIONS of Adam's descendants) was part of the plan from the beginning.