where does saying when in rome come from
When in Rome, do as the Romans do Saint Monica and her son, Saint Augustine, found out that Saturday was observed as a fast day in Rome, where they planned to visit. It was not a fast day in Milan, where they lived. They consulted Saint Ambrose who said "When I am here (in Milan) I do not fast on Saturday, when in Rome I do fast on Saturday." That reply is said to have brought about the saying "When in Rome, do as the Romans do."[4][5]
Mens sana in corpore sano The phrase comes from Satire X of the Roman poet Juvenal (10.356). It is the first in a list of what is desirable in life: