Sun-day / Sol dei – Roman venerable day of the sun. root Pagan.
“It has often been charged… that Catholicism is overlaid with many pagan incrustations. Catholicism is ready to accept that accusation – and even to make it her boast… the great god Pan is not really dead, he is baptized.” (The Story of Catholicism p 37)
“Cardinal Newman admits in his book that; the “The use of temples, and these dedicated to particular saints, and ornamented on occasions with branches of trees; incense, lamps, and candles; votive offerings on recovery from illness; holy water; asylums; holydays and seasons, use of calendars, processions, blessings on the fields; sacerdotal vestments, the tonsure, the ring in marriage, turning to the East, images at a later date, perhaps the ecclesiastical chant, and the Kyrie Eleison [Note 17], are all of pagan origin, and sanctified by their adoption into the Church. (374)” (An Essay on the The Development of the Christian Doctrine John Henry, Cardinal Newman, p.359)