In the beginning: The church of the first four centuries met in privately owned houses (Romans 16:5, 1 Corinthians 16:19, Colossians 4:15, Philemon 2).
Today ‘house churches’ are all the rage, but they aren’t anything like house churches in the New Testament. A modern house is generally the residence of a nuclear family, but a house in the Roman Empire was a much larger building that was not just the home of an extended family, its slaves, and employees, it was also the household’s place of business. A modern house church typically consists of a dozen or so people hunkered around the coffee table in the living room, some sitting on chairs dragged in from other rooms, but an ancient house church typically consisted of about 100 or so people standing in a large, mostly unfurnished public room called an atrium. Worship in a modern house church is very informal; from legal records of government raids on ancient house churches and the type of religious articles that they seized, we know that worship in an ancient house church was formal. The closest equivalent to an ancient house church is a modern church.
The front door of a Roman house was the public entrance for people who had business dealings with the household. It opened into a very large rectangular room—the atrium—that had a well, stream, or small pool just inside the entrance. The atrium could be very ornate, with a colorful mosaic floor and paintings of ancestors on the walls, but there was very little, if any furniture. On the other side of the atrium, opposite the front door, there was a raised platform that served as the household’s dining room with a chopping block front and center. There was no wall separating the dining room from the atrium, which allowed servants to attend to the diners from the atrium.
When the household was conducting its business, the atrium was a busy place, filled with people talking to each other and doing business with the household. Since the dining room was a raised platform without a wall separating it from the atrium, it was the best place for the father and his sons to conduct business. The father sat in the center behind the chopping block where he oversaw the proceedings, while his sons, seated on either side against the back wall, conducted the business of the household.
Hebrews 3:5-6 alludes to the different roles of servants and sons in the business dealings of the household:
Moses was faithful as a servant in all God’s house, testifying to what would be said in the future. But Christ is faithful as a son over God’s house. And we are his house, if we hold on to our courage and the hope of which we boast
—Hebrews 3:5-6, NIV
The sons, by virtue of being sons, had their father’s power of attorney, so whatever they did was binding on the father. Legally, so far as business deals were concerned, the sons were equal to the father:
For this reason the Jews tried all the harder to kill him; not only was he breaking the Sabbath, but he was even calling God his own Father, making himself equal with God.
—John 5:18, NIV
When a house was converted to a church, the water source at the entrance became the baptistery, the atrium became the nave, the dining room became the chancel, the chopping block became the altar, the bishop sat in the father’s seat, and the priests sat on either side. The house could accommodate a congregation of about 100-150 people. Pews were invented in the west in the middle ages. Orthodox churches still do not have seats in the nave.
If you would like to see a simplified version of a Roman house church, just look around you in your own church during Sunday worship (if it has the historic floor plan)!

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