Is anything too hard for the Lord? s1e91 Gen18:1

What is the BEST question in all of the Bible? You could certainly make an argument for this one: Is anything to hard for the Lord? God asks this of Abraham and Sarah. Funny thing though, is that God Himself KNOWS THE ANSWER to the question He asks.  However, Sarah and Abraham are wrestling with the answer, as should we. Please ask and answer it with me. 
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