I. History
1. Sunday (Lat. dies solis, Ger. Sonntag, Dutch zondag, Danish Søndag) is the second day of the Greco-Roman planetary week, which displaced the original Roman eight-day week in the 2nd century ce. Influenced by the model of the Jewish seven-day week but also by astrological notions from the Near East, it associated the days of the week with the seven known “planets” (including the sun and moon). As Mithraic religion and the cult of sol invictus (celebrated on Dec 25; introduced by th…