"I was in the Spirit on the Lord's Day..." (Rev. 1:10).
Someone has said, "Our great-grandfathers called it the holy Sabbath; our grandfathers, the Sabbath; our fathers, Sunday; but today we call it the weekend."
But John, on the island of Patmos near the end of the first century, calls Sunday the Lord's Day. The perfect name for it. The Holy Spirit, the Divine Author of all Scripture, calls it the Lord's Day. And may it be said of us, "They called it the Lord's Day." We can do this!
Why is Sunday called the Lord's Day? Because on it the Lord Jesus Christ rose. And so Sunday, as one scholar has put it, "was set aside from the very beginning as the most suitable day for Christian worship."
"The Lord's Day" is a call to the Christian congregation to come together around Christ who says, "I died, and behold I am alive forevermore" (Rev. 1:18). Nothing could be more beautiful and blessed than the Lord's Day in the Lord's House with the Lord's Word, the Lord's Prayer, and the Lord's Supper!*
What would happen if we started using this perfect name? If we said to each other, "See you on the Lord's Day!"? I'll tell you what would happen.
Attendance would go up. Faith, hope, and love would grow stronger. And our congregations would come alive at the feet of the Lord who is "alive forevermore"!
*It's worth noting that the Greek word for "Lord's" is used only twice in the New Testament: here in Rev. 1:10 ("the Lord's Day") and in 1 Cor. 11:20 ("the Lord's Supper").