Refusal to Do What the Prophet Commands is Kufr

I found this hadith on what Prophet Mohammad has commanded.  So if refusing to follow the commands of our most beloved Prophet means we are kufr then are we kufr by not following his every command.  I think these are things that every Muslim should be aware of.  Read this hadith and decide for yourself.

Once Rasulullah (PBUH) on entering the masjid saw one of the sahahba sleeping on one side.  He said to Ali (RA), "Wake him up so that he can make wudu."  This Ali (RA) did and then addressed the Prophet thus, "Oh Messenger of Allah, you are always first to hurry towards any good deed. Why did you not wake him up yourself?"  To this Rasulullah (PBUH) replied, "I fear on behalf that this man may refuse, and refusal to my command is kufr.  If he refused your command, it would not be kufr (disbelief)."

May Allah guide us to follow his commands and avoid disbelief.  The writing of this hadith frightens me as I must be better.