As a child I thought (mistakenly) that the Old Testament God was a cruel and angry God, and that the New Testament portrayed a kind a loving God.
Little did I know at that time how much the Gospel writers and Jesus used the Old Testament in their teachings. Especially Matthew. But all have some quotes.
I think that is one of the reasons most people shy away from the Old Testament. Every commandment ever given was given for our benefit by a loving and caring Father. One should read the Old Testament with the view that since God is love, what are we doing that is making God so angry or for what purpose was a command given? (Yes, even in Leviticus.) It gives a whole different perspective.