And the final nail in the coffin of Protestant Sunday keepers who mock Sabbath keepers:
The Catholic Church is Above the Bible in Authority:
Now in the matter of Sabbath observance the Protestant rule of Faith is utterly unable to explain the substitution of the Christian Sunday for the Jewish Saturday. It has been changed. The Bible still teaches that the Sabbath or Saturday should be kept holy. There is no authority in the New Testament for the substitution of Sunday for Saturday. Surely it is an important matter. It stands there in the Bible as one of the Ten Commandments of God. There is no authority in the Bible for abrogating this Commandment, or for transferring its observance to another day of the week.
For Catholics it is not the slightest difficulty. “All power is given Me in heaven and on earth; as the Father sent Me so I also send you,” said our Divine Lord in giving His tremendous commission to His Apostles. “He that heareth you heareth Me.” We have in the authoritative voice of the Church the voice of Christ Himself. The Church is above the Bible; and this transference of Sabbath observance to Sunday is proof positive of that fact. Deny the authority of the Church and you have no adequate or reasonable explanation or justification for the substitution of Sunday for Saturday in the Third - Protestant Fourth - Commandment of God.
Source: The Catholic Record, London, Ontario Canada, September 1, 1923, Diocese of Bishop Most Rev. Michael F. Fallon, D.D., LL.D.
And how exactly do you determine the seventh day?
Is it from midnight on the sixth day till the midnight on the seventh day?
Or is it sundown on the sixth day till sundown on the seventh day?
Which time zone does it apply to? Because when its the seventh day in one time zone, it is the sixth in another.
Galatians 5:2-4
King James Version
2 Behold, I Paul say unto you, that if ye be circumcised, Christ shall profit you nothing.
3 For I testify again to every man that is circumcised, that he is a debtor to do the whole law.
4 Christ is become of no effect unto you, whosoever of you are justified by the law; ye are fallen from grace.