firmness of purpose

NOUN
19 LETTERS · STARTS WITH F

firmness of purpose is a valid 19-letter word worth 29 points in Scrabble and 34 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS
F4I1R1M3N1E1S1S1O1F4P3U1R1P3O1S1E1
4 + 1 + 1 + 3 + 1 + 1 + 1 + 1 + 0 + 1 + 4 + 0 + 3 + 1 + 1 + 3 + 1 + 1 + 1 =29 PTS
DOUBLE WORD → 58TRIPLE WORD → 87
MEANING

What does firmness of purpose mean?