Biblical formality and festivity

Pastor Cathey quotes Pastor Sumpter who quotes  a scholar in the field of reformed worship:

“Since for Americans there is often an in-built negative reaction to any mention of formality in worship, let us turn briefly to Hebrews 12 and Revelation 4-5. Hebrews 12:22-24 describes a New Covenant (contrasted with the Old Covenant worship of vss. 18-21) corporate, Lord’s Day worship service. When the church gathers on the Lord Day she enters into heaven (by faith) to worship God with all of the angelic host and departed saints. It is as if the roof of the church building is torn off when the pastor calls the people to worship. Notice that the worshipers are all organized around the throne of God. The worship service does not merely provide an opportunity for private devotional experiences. The church is a ‘city’ and a ‘joyous assembly’ or ‘festal array’ (v. 22). The word translated ‘festal assembly’ denotes an assembly of people gathered for a celebration or festival. Later, when we are privileged with the Apostle John in the book of Revelation to peek into heaven, how is the worship conducted? What kind of worship is modeled for us in heaven? There are all kinds of liturgical lessons to be learned here. I only wish to highlight one aspect: the heavenly service is liturgical and formal. According to Revelation 4-5, heavenly worship is a formal, coordinated activity. There are cooperative, formal responses by groups of worshipers. Everybody responds together with the same words. There are no individual displays of spirituality. Angels, elders, and creatures respond antiphonally with responses that must have been learned! They have been trained. There is a pre-arranged form to the worship. They have rehearsed this event, and they are dressed accordingly (Rev. 4:4). In other words, heavenly, Spirit-guided worship is liturgical and formal (1 Cor. 14:26-33).”
G. Mark Sumpter