Great question! I don't believe the it's in the Bible response is good enough for this one. How I reconcile this in my mind is that God is sovereign,therefore He understands the purpose for what He decrees in ways I never will. Like it or not,understand it or not,I cannot say that anything God has ever done is wrong in the way mortals understand the concept of right and wrong.Not only that, but I believe God is just,therefore in His infinite wisdom He would give those people from the OT an opportunity for salvation.Just my 2 cents worth “Hell will be filled with people that didn’t cuss, didn’t drink, and may even have been baptized. Why? Because none of those things makes someone a Christian.”