When Sunday Became Sunday
Nobody told me Sunday was controversial.
I grew up going to church on Sunday the same way I grew up speaking English — as if it were simply the natural order of things, not a choice anyone had made. Sunday was when Christians gathered. Self-evident, like the sky being blue.
It took me an embarrassingly long time to notice that the Bible's actual day of rest is Saturday.
The Sabbath — the day God rested, the day the commandment protects — runs from Friday evening to Saturday evening. Not Sunday. And the first followers of Jesus were Jewish. They kept the Sabbath. They didn't have a theological reason to abandon it, and there's no evidence they did. For a while, at least, it seems they kept both.
So what happened? When did Sunday become Sunday — and why?
The answer starts at a tomb.
Mark's Gospel says the women came to the tomb "very early on the first day of the week." John says the same thing. The resurrection happened on the first day. And then it kept happening on the first day. The risen Jesus appeared to the disciples the evening of that same first day. Eight days later, it was again the first day when Thomas encountered him. Pentecost itself — fifty days after Passover by the Jewish reckoning — landed on the first day of the week.
The first day had become the day of meeting Christ.
It shouldn't be surprising, then, that when the earliest Christians gathered in expectation of meeting him again, they reached instinctively for the first day. Not because a rule said to. Because that was when it had happened.
By the time Paul writes to the Corinthians — sometime in the mid-50s — he can refer almost casually to "the first day of every week" as when people set aside their contributions. No explanation needed. The first day was already the gathering day. And somewhere in the book of Revelation, John mentions that his vision came to him "on the Lord's Day." Not the Sabbath. The Lord's Day. The phrase existed now — and so did the day it named.
What I find harder to trace — and more interesting — is what this cost.
For Jewish Christians, keeping both days was a real burden, not a scheduling inconvenience. Observing the Sabbath meant observing the Sabbath: no travel, no work, a full day structured around rest and Torah. Then coming back together on Sunday — after sundown Saturday, when the Sabbath ended — for the breaking of bread, the readings, the prayers. There are traces of exactly this in Acts 20, where Paul gathers with a community in Troas and they break bread on "the first day of the week," with Paul speaking through the night. On a Jewish reckoning of days — where the first day began at sundown Saturday — this would mean they were gathering as the Sabbath ended.
At some point — and this didn't happen everywhere at the same speed — Sunday won. The Sabbath, for Gentile Christians, had never carried the same weight. And as Gentile believers became the majority, the Jewish rhythms that had shaped the earliest gatherings began to fade. By the time Ignatius of Antioch — a bishop writing his final letters as he traveled toward martyrdom in Rome — writes around 110 CE, he describes Christians as those "no longer observing sabbaths but fashioning their lives after the Lord's day, on which our life also arose through Him."
That sentence is worth sitting with. No longer observing sabbaths. A sentence like that would have been unthinkable to the first disciples. It reveals how much had shifted in just a few decades.
I've thought about this shift often when I'm setting up for a Sunday service — standing in the room an hour before anyone arrives, checking monitors and arranging chairs. There's something that feels immovable about Sunday morning to me. Ancient. Like it was always this way.
It wasn't always this way. Someone made a choice, early and gradually, to gather on the day the tomb was found empty. And that choice carried something: an expectation. Not just that Christians would mark a day off the calendar, but that the one who had appeared on the first day might appear again. That gathering on Sunday was itself an act of anticipation.
That's a different frame than what I usually bring to Sunday morning. I tend to think about preparation — what's going to happen, what the service needs. The early Christians seem to have come with a different question altogether: who might show up.
Constantine famously made Sunday an official day of rest in 321 CE. He called it "the venerable day of the sun" — not even explicitly Christian. But Christians had been gathering on Sundays — alongside the Sabbath at first, then increasingly on Sunday alone — for nearly three centuries by then. The emperor didn't give them Sunday. He just noticed they already had it.
The day was not a gift from Rome. It was a habit formed in the habit of waiting.
And maybe that's worth something on a Sunday morning when I'm still setting up chairs and not yet thinking about much beyond whether the sound is balanced. The people who settled on this day weren't thinking about convenience or tradition. They were thinking about where they had met him before — and whether it might happen again.
