Do Protestant writers acknowledge the same?

Answer

They do.
NOTE - "IS there no express commandment for observing the first day of the week as Sabbath,
instead of the seventh day?-None whatever. Neither Christ, nor His apostles, nor the first Christians
celebrated the first day of the week instead of the seventh as the Sabbath."-New York Weekly Tribune,
May 24, 1900.
"The Scriptures nowhere call the first day of the week the Sabbath. . . . There is no Scriptural
authority for so doing, nor of course any Scriptural obligation." The Watchman (Baptist).
"The observance of the first instead of the seventh day rests on the testimony of the church, and
the church alone.' -- Hobart Church News, July 2, 1894.
For additional testimonies, see reading on page 146.

In what language is the justice of God described?
What is the basis of faith?
What promise is thus fulfilled?
What testimony did Christ bear concerning His relation to the law and the prophets?
Into what perplexity did Christ's working of miracles on the Sabbath throw the Pharisees?
What is to be finished when the seventh trumpet is about to sound?
When expiring on the cross, what did Christ say?

Questions & Answers are from the book Bible Readings for the Home Circle