I think the book took painstaking efforts to attempt to subvert the clear and unambiguous divine instruction to keep the SEVENTH-DAY SABBATH holy, as found in both the Old and the New testament of the scriptures and observed by Jesus Christ Himself who is LORD of the Sabbath.
Satan has always been the arch-deceiver of man right from Eden who deceived our first parents that "they will not surely die" when they disobey God's clear commandments and follow their own human inclinations.
That old serpent he still speaks through this book to lead most of God's wonderful human creation into disobedience of God's clear and immutable Seventh-day Sabbath commandment, which is God's rightful claim of being our creator and redeemer.
God is a spirit and they that worship Him must worship Him in spirit and in truth.
