WordNet sense 1 (a message that makes a pledge):

dedication

WordNet sense 2 (the trait of sincere and steadfast fixity of purpose):

committedness

WordNet sense 3 (the act of binding yourself (intellectually or emotionally) to a course of action):

allegiance, loyalty

WordNet sense 4 (the official act of consigning a person to confinement (as in a prison or mental hospital)):

committal, consignment