'Christianity says that all worship of God outside of Christianity is idolatry. And idolatry consists in this, that men worship that divine image which their own religious consciousness has made. They neither know the living God nor do they come in touch with Him in their religions.
'In Christianity God comes down to sinful man. The religions are nothing but man's vain attempts to lift himself up to God.'
--O. Hallesby, Religious or Christian (trans. C. J. Carlsen; Augsburg 1939), 190-91