One man once said History is a prophecy of the future, those who don't know it are bound to repeat it. So one way in which we can know the future apart from via prophetic foresight is by studying history. To better appreciate what God is going to do in the days ahead we can look at what he did in the past. In the field of literature, there is what they call flash forwards, where the writer will take you to the future and come back. God is against child/human sacrifice, yet at one point he said to Abraham go sacrifice, if I was Abraham I would have asked Him, how can you ask me to do something which you are against, but theologically we understand that he was kind of giving us a flash forward into what he will do in the future giving his only begotten son as a sacrifice. As we know that the old testament  is the new testament concealed and the new testament is the old testament revealed.