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.

I. What does Jesus declare Himself to be?
And what besides a mere belief in the truth is necessary?
What cheering message has Christ sent to His people touching His resurrection?
How are those described who heed this warning?
Had the Lord spoken regarding the Sabbath previous to this time?
12. Why did Job wish that his words were written in a book, graven with an iron pen and lead in the rock forever?
How many distinct classes will have a resurrection?

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