Where in the Bible does it mention worship should be orderly? Some churches seem to have no order or structure of worship. Respectfully submitted.
“Let all things be done decently and in order.” (1 Corinthians 14:40) To find out what this means we must look at the context of the chapter. In verses 29-33 he tells people not to speak all at once, even when they had a spiritual gift of prophecy. This would indicate that “decently and in order” is more about consideration for others than it is about structure.
In the first century assemblies of the church were often without structure as we would see it today. People might come and go at will. Somebody might start a song, then another person spontaneously pray or speak a message. It may have been more along the lines of what some today call “a devotional.” Most congregations did not have hired preachers, like we have today. There were probably no “worship leaders” or assigned duties. They apparently never heard of the required “three songs and a prayer” structure. That did not come in until many years later with the development of the Roman structure of worship and government (under the Orthodox and, later, the Roman Catholic churches).
An unstructured assembly is not wrong, as long as it is done in such a manner that only one person is speaking at a time (except that all may sing, if they are all singing the same thing). If one man is speaking and another has something to say, the first man should yield the floor. The idea of “orderly” or “in order” is one of waiting your turn rather than having a preordained structure.