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.

Upon what conditions is an understanding of divine things promised ?
Whose presence does the Holy Spirit bring to the believers?
How had they done this?
Was the Sabbath designed to be a day for public worship?
What is the object of the International Reform Bureau?
Through whom is this first dominion to be restored?
For what did Abraham look?

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