Here's a question: are the terms "Lord's Day" and "Sabbath" interchangeable?
It's interesting that one interpretation of Matthew 28:1 is "And on the eve of the sabbaths, at the dawn, toward the first of the sabbaths, came Mary the Magdalene, and the other Mary, to see the sepulchre" (YLT)
But I also find it interesting that Luke still refers to Saturday as the "Sabbath" throughout the book of Acts. Sunday is called "the first day of the week" or "the Lord's Day." The Early Church Fathers apparently called it the "eighth day," "the day of resurrection," or "the Lord's Day."
Of course, that doesn't mean they didn't treat the day as a sabbath, but it appears to me they did want to make a distinction between the OT shadow and the NT reality. Jesus is Lord of the Sabbath, so they wanted to name the day after Him!
And if the reality is far more glorious, why would we not want to spend it in corporate worship, prayer, rest, fellowship, doing good to our neighbor, etc? It ought to be our delight! Honestly, early on, when I first became a Reformed Baptist, I wanted a list of do's and don'ts for the Lord's Day, and I was personally uptight about it in many ways. But then I realized that, as Jesus said, this day was given for man, not the other way around. I realized that when I contemplate Christ and His Gospel, when I truly ask God to search me and try me and fill me with His Spirit, when I ask God to show me how I might serve and edify the Body, when I am aware that Christ is walking among His lamp-stands in our corporate worship, when I seek to fulfill the law of Christ by bearing the burdens of others, the need for a list basically disappeared. It's a reminder that we serve in the newness of the Spirit, not in the oldness of the letter!
Isaiah 58
13 “ If you turn away your foot from the Sabbath,
From doing your pleasure on My holy day,
And call the Sabbath a delight,
The holy day of the LORD honorable,
And shall honor Him, not doing your own ways,
Nor finding your own pleasure,
Nor speaking your own words,
14 Then you shall delight yourself in the LORD;
And I will cause you to ride on the high hills of the earth,
And feed you with the heritage of Jacob your father.
The mouth of the LORD has spoken.”
If this promise was given to Israel, how much more to us on the Lord's Day!