Invoked: The Captain reasons that division of labour is the best way to set up his unit, and somebody with conflicting objectives will work less effectively. So the guy in charge of keeping injured members alive is ordered to concentrate on that, and only fight to defend himself and his patients.
Deconstructed: Jack refuses to fight because he considers himself morally superior to those who do, although he completely relies on their defending him.
Reconstructed: His teammates throw him off for his attitude, only discover that they need his healing, that they are considerably more blood-thirsty without his calming influence, and that he has serenely gone on doing good without them. After a while, they realize that what they took for his attitude had really been their looking at him while possessed by the Green-Eyed Monster for his calm and collected manner and Incorruptible Pure Pureness.