Imagine you were given the opportunity to meet the Queen of England. It’s likely you wouldn’t wing it, arriving in your favorite comfy outfit to share some personal stories about your family dog. Instead, you’d probably study to find out what you are supposed to do when you were in her presence. Likewise, we should be thoughtful as to how we enter God’s presence in worship as a church body. During the Protestant Reformation (roughly 1517-1648), one of five key doctrines to emerge was sola scriptura, which is Latin for “Scripture alone.” This means that the Bible is our source of truth and provides our only infallible rule of faith and practice. This doctrine guards against elevating church tradition, personal experience, or reason to an equal level of authority with God’s revealed will in the Bible.
Scripture Guides Us
A primary purpose of God’s Word is the self-disclosure of Himself to His people. This includes how we are to worship Him with our lives, and how we worship Him in corporate worship—our time gathered with other believers on the Lord’s Day. Two primary schools of thought emerged during the Reformation: the earliest Protestant reformer, Martin Luther, applied sola scriptura to worship by saying that anything which may be edifying is permissible in gathered worship if it is not forbidden in Scripture: “I condemn no ceremony except such as are opposed to the gospel; all the rest I leave intact within the church.” This became known as the “Normative Principle of Worship” and is the prevailing approach to corporate worship in North American churches. Essentially it states that Scripture makes clear things we should not do in worship; that is, we should avoid anything obviously sinful. Many faithful Christians adhere to this worship philosophy, seeking to legitimately honor God’s Word in their worship by not violating God’s commands during their times of gathered worship.
However, another view became much more widely held among the “Reformed” (Protestant non-Lutheran) groups. It was eventually known as the Regulative Principle of Worship (RPW). This concept also applied sola scriptura, but instead of asking what we may do in gathered worship, it states Scripture is sufficient to tell us what we should do in worship. This principle states that God, through His Word, commands certain distinct elements for corporate worship, such as singing, praying, and preaching. Any additional elements not found in Scripture must be left out. There may be some variation in how the elements are executed (sermon length, number of songs, etc.), but the actual service components are those which are prescribed in Scripture.
The basis for this principle is that God is perfect, holy, and transcendent beyond our imagining; we are redeemed-yet-flawed created beings and cannot rightly come up with how we ought to enter His presence in worship. Instead, we must worship God together on His terms, according to His guidelines made known in His Word — especially through Jesus’ teachings, the apostles’ writings, and New Testament church practice carried out under apostolic oversight. The Regulative Principle emphasizes that we must not add to or take away from God’s Word  and “that worship is of God, by God, and for God.”
God Sets Our Boundaries
The Protestant Reformers consistently tied the First Commandment (“no other gods,” Exod. 20:3) to Whom we worship, and the Second Commandment (“no graven images,” Exod. 20:4-6) to how we worship. French theologian John Calvin said: “although Moses only speaks of idolatry [here], yet there is no doubt that by synecdoche [mentioning a part of something to refer to the whole], as in all the rest of the Law, he condemns all fictitious services which men in their ingenuity have invented.” 
The Reformation-era confessions and creeds, although not divinely inspired, do helpfully summarize key Bible teachings as understood by the Reformers who sought to correct major theological errors in the medieval church… [Read the rest!]