The figures of every religious culture are necessarily secularized and recede. They can keep themselves alive only as ideas, symbols, and ghosts, and finally comic figures. And in the end even in this form they sink into oblivion. No sentence is more dangerous or revolutionary than that God is One and there is no other like Him…There is no more room now for what the recent past [referring to the 19th century] called toleration. Beside God there are only His creatures or false gods, and beside faith in Him there are religions only as religions of superstition, error and finally irreligion.
— Karl Barth, Church Dogmatics. [II, I, p443f]