Mysterio…
Because Catholics are Christians not Jews, the entire Old Covenant was done away with. However, the church has chosen to incorporate some parts of the old covenant in the new, and did that by giving us worship on the Lords Day. You will find that there no command for any Christian to observe the Jewish Seventh-Day Sabbath in scripture. Jew’s, yes, but Christians (i.e. followers of Christ after his death and resurrection) were never commanded to do this.
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