These big agreements between denominations are vitally important; yet, for all the talk about denominational communion, there is one sign of that union most Christians around the world experience every single Sunday in their pews, tent meetings, Masses, revivals, and preaching services across an eye-popping variety of traditions. Every week, it shows us that Jesus’ prayer is being answered all the time. I am talking about the Revised Common Lectionary.

We hear it every Sunday, but I will bet that most laity, and for that matter many clergy, may not realize that the Scriptures being heard in our parishes are very likely being heard in a neighboring congregation of another tradition next door, across town, and around the world.

Of course, there are variations. Depending on which lectionary one’s parish uses, the Episcopal lectionary may differ somewhat from the RCL, as does the Roman Catholic lectionary on which it is based. Individual pastors and parishes may tweak it here and there according to their needs and emphasis, but the fact is that we are sharing something very basic.

If you stop and think about how many Christians around the world are hearing, reading, and praying the same Scriptures every single week, it is nothing short of amazing.

This was driven home to me once when I was on vacation. I decided to visit a church to surprise a college and high school friend, who was a Baptist pastor, and hear him preach. It was the middle of summer and, much to my surprise, the Gospel text he chose to preach from (with that deep scriptural exposition common in his tradition) included the same Gospel text I would have heard had I walked into an Episcopal Church.

He even wrapped it up nicely and listed the series of texts in that venerable tool, “A Sermon Series” complete with an outdoor banner and a catchy title — which is provided for in the way the RCL is designed.

After the service, we were talking over lunch, and I commented on that fact. I can’t remember my exact words, but I asked him something like this: “In your tradition, you could have chosen any passage you wanted from the whole Bible. Why did you choose this?” The answer was that it was easy. This was where all the supporting material was there to be found: commentaries, hymn selection resources, bulletin covers, adult education, and Sunday school materials for the kids and youth were all (even nominally) keyed to the themes found in the RCL.

Sure, his tradition’s materials and mine are different in their presentation, emphases, and nuances; his preaching and even his theology differed from mine. We could talk for hours about where our theologies met and diverged as we follow the same Christ, under One God, listening in our own way to the same Spirit and we discussed (and, yes, argued about) the big issues facing the church today. But, because we shared the same lectionary, we were in our own way reading, struggling with, and praying about the same Scriptures every week.

About that time, I was also part of a local ecumenical coffee klatch that talked about the next week’s Bible passages, and I found the same thing. It was like the start of your basic religious joke: each week, a Catholic, Episcopalian, some Protestants, and a Unitarian would gather for coffee, study, pray, and sometimes play golf. And when we talked about Sunday, we all were, for the most part, following a similar calendar, reading the same Scriptures.

If you think about it, that is a remarkable achievement! The Revised Common Lectionary has become a practical, useful, expression of Christian unity that permeates the everyday lives of everyday believers every single week.

And it is so natural that we hardly even notice.

The Rev. Canon Andrew Gerns is a priest in the Diocese of Southwest Florida.