Now let us define the lawful worship of God. Indeed, its chief foundation is to acknowledge Him just as He is—the only source of all virtue, righteousness, holiness, wisdom, truth, power, goodness, mercy, life, and salvation. It is, moreover, to attribute and assign the glory of all things entirely to Him, seeking all things in Him alone. Finally, it is, when we have any need, to lift it up to Him alone. Invocation is born from this, and from it flow praises and thanksgiving, which are testimonies of that glory that we attribute to Him. This is the true hallowing of His name, which He requires of us above all. Adoration is connected to this, by which we show to Him reverence that is worthy of His greatness and excellence. Ceremonies serve this, whether as props or means, so that the body may be exercised together with the soul in the profession of divine worship. The denial of ourselves follows next, so that renouncing the flesh and the world, we may be transformed unto the newness of mind. The purpose of this is that we may no longer live for ourselves but resign ourselves to Him to rule and lead us. Moreover, by this self-denial we are made ready for obedience and deference to His will, so that the fear of God may reign in our hearts and guide all the actions of our lives. These elements contain the true and sincere worship of God. The Holy Spirit approves of and delights in this alone, which He teaches everywhere in Scripture. The very notion of godliness teaches the same without a long disputation. Moreover, from the beginning there has been no other method for worshiping God than what this spiritual truth, which is plain and simple before us, entailed in types under the Old Testament. This is also what Christ’s words mean in John 4, “The time has come when true worshipers will worship the Father in Spirit and in truth” (John 4:23). To be sure, with those words He did not mean to deny that worship had existed in that spiritual manner among the Patriarchs but only to indicate a distinction in outward form. For, although they had foreshadowed the Spirit with many types, it is simple among us. Otherwise, this always prevailed: it is necessary that God, who is Spirit, be worshiped in Spirit and in truth.
Therefore, the rule that distinguishes pure worship of God from its corrupted form is universal: we must not mix in what has seemed good to us but must observe what He requires who alone has the authority to command. Therefore, if we want Him to approve our worship, we must carefully keep this law that He enforces with utmost severity. The reason is twofold that the Lord, by forbidding and condemning all man-made worship, calls us back to obedience to His voice alone. For (1) this greatly applies to establishing His authority, so that we may not serve our own wills but rely entirely on His will, and (2) we are so proud that, if freedom is left to us, we can do nothing but go astray. Moreover, once we have turned aside from the way, afterward there is no end as long as we are buried in a multitude of superstitions. Therefore, the Lord, so that He may claim the full right of lordship for Himself, rightly commands us to do what He wills, so that He refuses whatever humans have devised that is beyond His command. He also rightly does this because He blocks off limits for us with His mouth, lest by inventing corrupt worship, we provoke God’s wrath toward us. This is so difficult to persuade the world of: God disapproves of all worship that has been established beyond His Word. Instead, this persuasion prevails and is as it were formed in the bones and marrow of all people: whatever they do they have sufficiently just approval for it, provided they display some zeal for the glory of God. But since God not only considers empty but also openly hates what we support for worshiping Him beyond His command, what do we profit by doing anything to the contrary? These are the clear and distinct words of God. Obedience is better than sacrifice (1 Sam. 15:22). He is worshiped in vain through the commandments of men (Matt. 15:9). Whatever is added to His Word is a lie, especially in regard to mere will-worship (ἐθελοθρησκείαν), which is emptiness. Once the judge has made a pronouncement, there is no longer any time for dispute.