Moltmann says that if we assume a rigid defensive stance regarding our doctrine, it is actually cowardly.
The decay of faith and its identity, through the a decline into unbelief and a different identity, forms an exact parallel to their decay through a decline into a fearful defensive faith. Faith is fearful and defensive when it begins to die inwardly, struggling to maintain itself and reaching out for security and guarantees. In so doing, it removes itself from the hand of the one who has promised to maintain it, and its own manipulations bring it to ruin. This pusillanimous faith usually occurs in the form of orthodoxy which feels threatened and is therefore more rigid than ever. It occurs wherever, in the face of the immorality of the present age, the gospel of creative love for the abandoned is replaced by the law of what supposed to be Christian morality, and by penal law.
He who is of little faith looks for support and protection for his faith because it is preyed upon by fear. Such faith tries to protect its 'most sacred things', God, Christ, doctrine and morality, because it clearly no longer believes that these are sufficiently powerful to maintain themselves. When the 'religion of fear' finds its way into the Christian church, those who regard themselves as the most vigilant guardians of faith do violence to faith and smother it.
Jurgen Moltmann, The Crucified God, pp. 11-12.