The quote below was very eye opening for me. While the context is the call of unilateral nuclear disarmament, i can see how it would apply to even the most ordinary of situations, such as the local ministry of the Church, or even our own personal sacrifices, or lack thereof.
It is easy to talk ourselves out of commitment or demonstrating love when we can appeal to the logic of possibility [what if...?]. "If i do this, what if that?" If i give $1.50 to that homeless man, then he might spend it on booze." "If i adopt that child, he might get bigger and abuse my boy, due to some unknown or subconscious psychological difficulty we weren't aware of." The realm of "possibility" is often an excuse for poor behavior, or more often, lack of virtuous behavior.
In the current discussion on armament control, many arguments are based on the question of what is possible rather than on what is probable. The difference between these two modes of thinking is precisely the difference between paranoid and sane thinking. The paranoiac’s unshakable conviction in the validity of his delusion rests upon the fact that it is logically possible, and, so, unassailable. It is logically possible that his wife, his children and colleagues hate him and are conspiring to kill him. The patient cannot be convinced that his delusion is impossible; he can only be told that it is exceedingly unlikely. While the latter position requires an examination and evaluation of the facts and also a certain amount of faith in life, the paranoid position can satisfy itself with the possibility alone. I submit that our political thinking suffers form such paranoid trends. We should be concerned, not with the possibilities, but rather with the probabilities. This is the only sane and realistic way of conducting affairs of national as well as individual life.
Erich Fromm, The Case for Unilateral Disarmament, 1960