Luther started the Protestant Reformation in 1517. However, in the year before his death the Romish Council of Trent started giving its reply, in 1545.
This resulted in the 1562 Catechism of Trent, which is still Rome's official doctrine even today. There, it is wrongly alleged that the weekly sabbath was not "a natural principle" alias a creation ordinance. Instead, the weekly sabbath is averred to have existed only "from the time the people of Israel were liberated from the bondage of Pharaoh."
Furthermore, Rome there even claims that the obligation to keep the weekly sabbath was destined "to cease together with the abrogation of other Jewish[!] rites and ceremonies namely at the death of Christ.” For “it has pleased the Church[!]…that the religious celebration of the sabbath day shall be transferred to the Lord’s day” and the “other[!] days."1
These "other days" are not the Old Testament Feasts instituted for Israel by God in His Word. These "other days" are Romish festivals instituted for Romanists by the Deformed Church only millenia later. As the 1542-1621 Cardinal Archbishop Bellarmine of Capua stated in his own Catechism anent the 'Third[!] Commandment': "Remember the festivals, to keep them holy."
Thereby, the Christian Sabbath of Holy Scripture was ignored. Matt. 28:1; Mark 16:2,9; Luke 53:56 to 24:6; John 20:1,19,26; Acts 2:1; 20:67; I Cor. 16:1-2; Heb. 4:8-11 cf. 10:25; Rev. 1:10. Thereby, the Lord's day was, and is, degraded to the level of the saints' days appointed by Mediaeval Romanism. Thereby, Jesus Christ the only-begotten Son of God the Father was, and is, rather is demoted to the standing of mere mortals like "St." Teresa!
This then was, and is, Rome's answer to the Reformation. This was, and is, the reply to the Reformed Church of the Deformed Church alias that part of the Church that refused to reform (and still refuses to reform) according to God's Word. After the light of Luther at the dawn of the sixteenth century, there followed the darkness of Trent. Post lucem, tenebrae. But in the merciful providence of Almighty God, the Lord's day was again destined to be illuminated by the Sun of Righteousness (Mal. 4:2-4f). Post tenebras, Lux!
1 H.J.W. Legerton: The Church of Rome and the Lord's Day, Lord's Day Observance Society, London, 1957, pp 5-9.
CALVIN ON THE WEEKLY CHRISTIAN SABBATH
Doubtless it was the light received by John Calvin of Geneva (150964) which gave the death-blow to the Romish festivals and great impetus to God's Decalogue and to Sunday observance. Even in his famous Institutes first published when Calvin was but 27 years old he has fully seven(!) long paragraphs on the sabbath.2 A brief analysis of some of this material before we go on to other later material authored by Calvin will now be very helpful.
In his Institutes, Calvin grounds the Lord's day in the weekly Sabbath. Against Rome, he insists that the ordinance of the Sabbath was not instituted merely at Sinai and solely for the Hebrews. To the contrary, he insists it was instituted at creation, in the seven days of our earth's formation and as an ordinance for the entire human race.
Observes Calvin:3 "Should any one expect some secret meaning in the number 'seven' this being in Scripture the number for perfection it may have been selected not without cause to denote perpetuity[!]. In accordance with this, Moses concludes his description of the succession of day and night on the same day on which he relates that the Lord rested from His works." Genesis 2:1-3.