Holy Ground!
The Old Testament is full of types and shadows of New Testament truth. Whenever I have a difficult time trying to understand a truth from the New Testament, I turn back to its foreshadowing in the Old. In fact, I believe there isn't a single episode or story in the Old Testament that is not full of ripe truth for New Testament believers.
My preacher grandfather once told me, "David, if you're going to teach about character, you have to go to the Old Testament. That's where all the character teaching is." I believe he was right.