I believe the argument above provides a biblical basis for treating the first day of the week not merely as a time for corporate worship, but also as a Sabbath. This reflects the teaching of our the Westminster and Second London Baptist confessions. We must note, however, that the biblical basis or warrant for a first day New Covenant Sabbath is established neither by the data of the NT alone nor by any explicit command alone. As Richard Barcellos notes, “This issue … cannot be decided upon one proof text for or against. Each text comes in a wider context in the book it appears in and, in its widest sense, a canonical context.” [“The New Testament Theology of the Sabbath,” Reformed Baptist Theological Review 5:1 (2008): 63] So good and necessary inference is an essential part of the argument.
For those, like myself, who agree that warranted inference is a legitimate form of argument, a first day Christian Sabbath can make sense. I can appreciate the Christian who wishes for an explicit command. However, the absence of an explicit command need not preclude such a believer from understanding the Lord’s Day as sabbatic in character. Perhaps some Christians are hesitant to view the Lord’s Day as a “Sabbath” because they think Sabbath-observance entails a long, dreary, and legalistic list of “don’ts.” I can sympathize with their concern. But I suspect their view of Sabbath-observance may be based on a misunderstanding of what the Bible actually teaches. A proper consideration of the biblical data enables one to view Sabbath-observance as a delightful “holi-day” (Isa 58:13). For more along these lines, click here.
The link provided by Bob at the end of that article is for the second article I would like to recommend. This is an article about proper Lord's Day observance, and it is entitled Does All Worship and No Play Make Jack a Holy Boy? Sabbath-keeping according to Isaiah 58:13. I highly recommend reading both articles. My thanks to Bob for writing them!