i don’t deny you won’t find a group here and there at various times that kept the 7th day sabbath.
what i do deny is that the Christian Church ever did, as no one in the NT ever kept the sabbath after Pentecost and the Catholic Faith received from the Apostles did not include keeping the sabbath.
Not so. It was the normal practice of the biblical church to keep the sabbath. The best example of this is in Acts:
Act 13:42 So when the Jews went out of the synagogue, the Gentiles begged that these words might be preached to them the next Sabbath.
No doubt in their minds WHEN to congregate. On the sabbath. Makes perfect sense since this was found in scripture and was the practice of those who worshipped the true God.
Act 13:43 Now when the congregation had broken up, many of the Jews and devout proselytes followed Paul and Barnabas, who, speaking to them, persuaded them to continue in the grace of God.
Act 13:44 On the next Sabbath almost the whole city came together to hear the word of God.
The whole city came when...on the sabbath. It was THE day recognized as belonging to the Lord of heaven and earth. There is and was no other.