Deuteronomy 6:13

13.Thou shalt fear the Lord thy God. Hence it is more evident why He has just declared that there is One God, viz., that He alone may be undividedly worshipped; for unless our minds are fixed on Him alone, religion is torn, as it were, into divers parts, and this is soon followed by a labyrinth of errors. But, first, he calls for reverence, and then for the worship which may testify and demonstrate it. “Fear” contains in it the idea of subjection, when men devote themselves to God, because His terrible majesty keeps them in their proper place. Hence results worship, which is the proof of piety. But we must observe that the fear enjoined in this passage is voluntary, so that men influenced by it desire nothing more than to obey God. When I stated, therefore, that God brings us under the yoke by a sense of His power and greatness, I did not understand that a violent and servile obedience is extorted from us; I only wished to affirm that men cannot be induced to obey God, before they have been subdued by fear; because their innate corruption always carries with it a contempt for religion, and a spirit of licentiousness. Therefore, in Jeremiah (Jeremiah 5:22), in order to exhort men to fear, He sets forth His terrible power in restraining the strength of the sea; but this fear leads on His true worshippers further. In the other passage which we have subjoined from Deuteronomy 10:0, the word cleave again confirms the truth, that as soon as men decline from God in the least degree, His worship is corrupted. For this is the meaning of that union with Himself to which He calls His worshippers, that they should be, as it were, glued to Him, and should not look elsewhere.