Roman Catholic
“It is well to remind the Presbyterians, Baptists, Methodists, and all other Christians, that the Bible does not support them anywhere in their observance of Sunday. Sunday is an institution of the Roman Catholic Church, and those who observe the day observe a commandment of the Catholic Church.” Priest Brady, in an address, reported in the Elizabeth, NJ ‘News’ on March 18, 1903.
"The Church, on the other hand, after changing the day of rest from the Jewish Sabbath, or seventh day of the week, to the first, made the Third Commandment refer to Sunday as the day to be kept holy as the Lord's Day. The Council of Trent (Sess. VI, can. xix) condemns those who deny that the Ten Commandments are binding on Christians."
The Catholic Encyclopedia, Commandments of God, Volume IV, © 1908 by Robert Appleton Company - Online Edition © 1999 by Kevin Knight, Nihil Obstat - Remy Lafort, Censor Imprimatur - +John M. Farley, Archbishop of New York, page 153.
'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... The Church is above the Bible, and this transference of Sabbath observance is proof of that fact.'' Catholic Record, September 1, 1923.
“If Protestants would follow the Bible, they would worship God on the Sabbath Day. In keeping the Sunday they are following a law of the Catholic Church.” Albert Smith, Chancellor of the Archdiocese of Baltimore, replying for the Cardinal, in a letter dated February 10, 1920.