There is no religion without revelation. Scripture too derives subjective religion from revelation (Heb.1:1). It is, for that matter, perfectly natural that religion and revelation consistently go together and are most intimately connected. For if religion really contains a doctrine of God and of his service, it is self-evident that God alone has the right and ability to say who he is and how he wants to be served. “It is not the part of men to establish and shape the worship of God, but, having been handed down by God, it is for them to receive and maintain.”* Religious indifferentism assumes that it is immaterial to God how he is served. It deprives him of the right to determine the manner of his service; in any case it postulates that God has not prescribed the manner of his service. —Herman Bavinck, Reformed Dogmatics
*Helvetic Confession
No Other Boast 