The Collaborative International Dictionary of English v.0.48:

Thankworthy \Thank"wor`thy\, a.
   Deserving thanks; worthy of gratitude; mreitorious.
   [1913 Webster]

         For this thankworthy, if a man, for conscience toward
         God, endure grief, suffering wrongfully. --1 Pet. ii.
                                                  19.
   [1913 Webster]