Source : Webster's Revised Unabridged Dictionary (1913)

Self-command \Self`-com*mand"\, n.
   Control over one's own feelings, temper, etc.; self-control.

Source : WordNet®

self-command
     n : the trait of resolutely controlling your own behavior [syn:
         {self-control}, {self-possession}, {possession}, {willpower},
          {self-will}]