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.

Can man free himself from the dominion of sin?
What was foretold of His treatment while on the cross?
What did Christ indicate as essential to eternal life?
Who has borne our sins, and stands ready to help us?
What was Messiah to do during the seventieth week?
What has been promised in order that man may be redeemed from this condition?
What encouragement does Jesus give us to meet cheerfully the troubles and trials of life?

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