Some claim that the Catholic Church changed the Sabbath from Saturday to Sunday. But this seems not to be the case. What the Catholic Church has done is not recognize the Sabbath (Jewish Sabbath) as binding on the Christian Church. The Catholic Church recognizes the Lord’s Day which has its basis in Jesus resurrection. The Lord’s Day is the first day of the week rather than the seventh day of the week as Jesus rose on the first day of the week.
I did find a reference to a Catholic Council that did issue some rules to the Catholic Church that are unwise and unsound. This reference is given at the end of the document and it is entitled Synod of Laodicea (4th Century); this synod or council is believed to have taken place around 363-365 AD.
The reference has a list of Catholic Canons which are at best described as regulations or rules concerning the church assemblies and church member behaviour when not in assembly. Canon 16 says “The Gospels are to be read on the Sabbath [i.e. Saturday], with the other Scriptures.” And Canon 29 says “Christians must not judaize by resting on the Sabbath, but must work on that day, rather honouring the Lord’s Day; and, if they can, resting then as Christians. But if any shall be found to be judaizers, let them be anathema from Christ.” And Canon 49 says “During Lent the Bread must not be offered except on the Sabbath Day and on the Lord’s Day only.” The word anathema is a Greek word that has the sense of accursed, banned, excommunicated, etc. In Galatians 1:9 Paul uses it and it is translated accursed in the KJV. In 1 Cor 16:22 Paul uses it in relations to divine judgement but it is not translated at all but is left Anathema by the KJV translators.
First note that the Catholic Canon 16 recognizes Saturday as the Sabbath and does not do away with Saturday as the recognized Sabbath. Secondly note that Catholic Canon 29 unwisely prohibits Catholics from resting from work on the Sabbath claiming that to do such a thing would be judaizing where judaizing refers to following Jewish customs and religious rites. Such a prohibition clearly recognizes Saturday as the Sabbath but imposes unsound doctrine upon the Catholic Church membership. In essence these Canons are consistent with my observation that the Catholic Church considers Sunday to be The Lord’s Day and not the Sabbath and has not done away with the Sabbath but rather unwisely and unsoundly prescribes such rules/canons concerning the Sabbath and the Lord’s Day, both of which they at least once held as days of worship or honoring God in the 4th Century.
Now what about today. Well in the 1983 Catholic Code of Canon Law there seems to be no mention of the Sabbath at all. The emphasis is clearly on the Lord’s Day as the prominent day of rest and worship. Exactly when this deletion took place within the Catholic Church between the Synod of Laodicea in the 4th Century and 1983 is unclear. The Catholic Church position now is seemingly not to prohibit rest on the Sabbath as they do not specify punishment for those who do. Instead they seemingly just encourage rest on the Lord’s Day. So even though they omit any mention of the Jewish Sabbath that is better than officially documenting unsound doctrine of prohibiting rest on the Sabbath Day. So in that regards the 1983 is markedly better than the 4th Century one. Of course Catholics have the bible to teach them about the Sabbath which of course is superior to the Code of Canon in God’s eyes though not in Catholic official position. For they unwisely and unsoundly claim that their oral tradition is superior to that which is written in scripture or at least what others think is written in scripture and what it means. To me, scripture is supreme for scripture says there is no private interpretation; that means the Catholic Church cannot rightly claim it is the only one that can properly interpret scripture although according to my understanding it does make such claims and if so wrongly does so. Indeed, every church struggles to properly follow the Holy Spirit in interpreting scripture as we strive against sin including the sins of selfishness and arrogance.
In summary, the Catholic Church at least as far back as the 4th century recognized both the Sabbath (Saturday) and Lord’s Day (Sunday) as appropriate for certain but not all worship elements. However, the Catholic Church errored in prohibiting its members from resting on the Sabbath. At least my 1983 the Catholic Church seemingly only recognizes the Lord’s Day but not the Sabbath Day. I consider the Lord’s Day as the Christian Sabbath although the Catholic Church does not view it as such. My regular day of community worship is Sunday;. However, I consider any day as appropriate for community worship. Therefore, I do not find it problematic for those such as Seventh Day Baptist or Seventh Day Adventist or “Black Hebrew-Israelites” and others who choose Saturday as their regular day of worship. See my article on the Christian Sabbath or Lord’s Day.