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.

What is felt in heaven when a sinner repents?
Why did the apostle say this duty was so imperative?
What will be the fate of those who do not obey the gospel of Christ?
What is the character of this new power?
How does Paul give expression to this hope?
How is the fifth trumpet, or first woe, introduced?
Where did he say he would wait?

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