I don’t really know that much about Marcion, but after reading about Moses and the Israelites (or would it be more clear to say Moses versus the Israelites) in the first five books of the Bible, I have to say that I can see why Marcion had questions about the Old Testament. Though I don’t agree that there are irreconcilable differences between the Old and the New, I sense the conflict and questions.
As a piece of dry grass proudly daring to approach the sun, it is a terrible thing for uncovered man to experience the intense, consuming fire of G-d’s holiness. Pride is humiliated and returns to the dust from which it was formed. Yet we are not without hope. In Christ, we are covered. In Christ, the bush burns eternally yet is not consumed.