When Moses knew that time for him was running out, he gave a charge to Joshua, saying, "Now what I am commanding you today is not too difficult for you or beyond your reach" (Deuteronomy 30:11).  As a man who knew his days--possibly even his hours—were numbered, he gave it to him straight.  He said that obedience is a choice, a decision which you make.  And with obedience comes blessing; with disobedience comes difficulty.