Science progresses because scientists, instead of running away from such troublesome phenomena or hushing them up, are constantly seeking them out. In the same way, there will be progress in Christian knowledge only as long as we accept the challenge of the difficult or repellent doctrines. A ‘liberal’ Christianity which considers itself free to alter the Faith whenever the Faith looks perplexing or repellent must be completely stagnant. Progress is made only into a resisting material.