Yes, this is one of those purely hypothetical, impossible to achieve in reality, questions. No one could start from absolute zero. We all bring experiences and ideas from our past when we approach the subject of worship. The early church obviously did this. We necessarily do it. Everyone has certain things that they view as normal and essential, before they even begin thinking about what Christian worship should be like.
But what if we could wipe the slate clean and start over? Let’s say that we got a copy of Scripture (preferably not bound in black leather and free from verse numbers and chapters). If we could approach Christian worship from a completely objective point of view, what conclusions would we draw from Scripture alone? What practices would we discern as appropriate? What things would be seen as necessary? What would our assemblies look like, if we had assemblies at all?
It’s an interesting exercise to try and think about that. I’m not arguing that we should approach worship in this way; I’m not even saying it’s possible.
Still, I think it’s healthy to think about it. If a people with no experience with worship of any sort received God’s Word and wanted to live by it, what would their worship look like?