Porque os dias da semana têm nomes cristãos?

Why do “domingo” and “sábado” break Portuguese’s weekday pattern?

Portuguese numbers its weekdays — segunda-feira, terça-feira — but domingo and sábado break the pattern, and both names are religious fossils. Domingo comes from the Latin dies dominicus, “the Lord’s day,” marking Sunday as sacred to early Christians. Sábado traces even further back, through Latin sabbatum to the Hebrew Shabbat, “rest” — the same root behind the English “sabbath.”

The other five weekdays are counted from Sunday: segunda-feira is literally “second (holy)day,” terça-feira “third,” and so on through sexta-feira, “sixth” — a numbering system that survived from an early Christian calendar reform while most other Romance languages (Spanish lunes, French lundi) kept the old Roman planet names instead.