Of course churches in Paul's day weren't anything like churches today. Based on the information I've found, it doesn't look like the early churches even had buildings.
The church in Rome didn't have a building? Why not?
Not because church leaders understood from the very beginning that there could be no building without first forming FINANCE and BUILDING COMMITTEES, but because the early Christians were often targets of political and religious persecution.
Having a big new building where the faithful dutifully assembled at 11 AM every Sunday morning would've made the job of arresting the entire congregation and hauling them off to jail an easier task than deciding what color to paint the church bathrooms.
So the early churches most likely met in peoples' homes, and their services included singing hymns, reciting scripture and creeds, praying, and praising God.
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The more I thought about it, the more I wondered whether the first Christians set their finest robes aside on Saturday nights, and dressed up for church. I kinda doubted it.
Not just because Peter and Paul warned against it, or because dressed-up people tended to be in palaces, but also because sneaking around all dressed-up on Sunday mornings between 10AM-12PM would've tipped off the Persecution Police.
So when did steeples, stained glass windows and dressing-up become rock solid trademarks of "church"?