"WHAT IS THE BIBLICAL DEFINITION OF WORSHIP?"
First, you can't reduce the definition of worship to one or two sentences. That would be like trying to reduce the definition of a "safe and legal car" to one or two sentences.
Second, among us Lutherans, we answer questions on the basis of Scripture with reference to the Confessions. Reference to the Confessions mainly avoids having to "reinvent the theological wheel."
Third, the English word "worship" is one of those undefined fundamental words that even a kindergarten kids knows, "It's what we do on Sunday morning in church."
Fourth, if you complain that I am avoiding the constraints of your question, Jesus did that all the time! :)
Fifth, our Lutheran confessions succinctly give the purpose of worship: "Places, times, persons, and the entire outward order of worship are therefore instituted and appointed in order that God's Word may exert its power publicly." (LC 3rd Comm, 94; Tappert, 378); and to hear, learn, retain, seriously ponder, and put to use the Word of God (LC 3rd Comm, 95-102; Tappert, 378-379).
Sixth, the "entire outward order of worship," is structured on these biblical principles:
a) First, Second, and Third Commandments, as explained in the Small and Large Catechisms.
b) The Lord's Prayer, as explained in the Small and Large Catechisms.
c) The Three Sacraments, as explained in the Small and Large Catechisms.
d) Various principles and rules found throughout the New Testament, particularly 1 Corinthians 11, 1 Corinthians 14, and Colossians 3:16.
Seventh, Lutherans recognize that all who follow the fifth and sixth points (above) conduct Christian worship, though there may be some error involved here and there. Some churches have significant error in worship, such as the Reformed denial of the Lord's Supper (i.e., denial of its nature, power, and benefits) and the Roman Catholic invocation of the saints (against the 1st commandment).
Eighth, Lutherans do not eliminate traditions of the "entire outward order of worship," but rather affirm traditions of the Christian church. This is in contrast to the Reformed religions deriving from the Anabaptists, Zwinglians, and Calvinists, who reject all traditions in principle. The Apology of the Augsburg Confession states that: "The holy Fathers . . . instituted [traditions] for the sake of good order and tranquility in the church." (Ap XV, 13; Tappert, 216). "The holy Fathers . . . observed these human rites because they were profitable for good order, because they give the people a set time to assemble, because they provide an example of how all things could be done decently and in order in the churches [1 Cor. 14:40] and finally because they helped instruct the common folk. For different seasons and various rites serve as reminders [i.e., memory aids] for the common folk. For these reasons the Fathers kept ceremonies and for the same reasons WE ALSO BELIEVE IN KEEPING TRADITIONS. . . . This good order is very becoming in the church and IS THEREFORE NECESSARY" (my emphasis; Ap XV, 20-22; Tappert 218). The Formula of Concord echoes and affirms the Apology when it says that ceremonies and church rites serve good order, decorum, preserve Christian discipline, and the edification of the church (FC SD, X, 1, 7, 9; Tappert, 610-612).
Ninth, Lutherans accept change in worship, so long as the changes:
a) serve good order, decorum, preserve Christian discipline, and the edification of the church (FC SD, X, 1, 7, 9; Tappert, 610-612).
b) are not contrary to God's Word (FC SD X, 5; Tappert, 611).
c) are not useless and foolish spectacles (FC SD X, 7; Tappert, 611).
d) do not give the impression that the Lutheran church is not greatly different from other religions or denominations (FC SD X, 5; Tappert 611).
e) do not give the impression that opposing religions or denominations agree with the Lutheran church, or that agreement will gradually result due to the use of these worship practices (FC SD X, 5; Tappert, 611).
Tenth, for further study, you can look at the Index in Tappert, under the topics of Worship, Ceremonies, Human Traditions, and Holy Days. Also the recently published book by Dr. James Brauer of Concordia Seminary, Saint Louis "Worship, Gottesdienst, Cultus Dei." It is an excellent resource for seeing all the passages in the Lutheran Confessions which pertain to worship, and therefore the full treatment of the Bible's understanding of worship from a Lutheran perspective.
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Yours in Christ, Martin R. Noland
