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 receiving the Son what do we have in Him?
Against what are husbands cautioned?
Who did He say would be called great in the kingdom?
After conferring over this matter, what decision was reached by the apostles?
What is to endure throughout all generations?
How was the matter finally decided?
What promise did Christ make concerning His coming?

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