Ember days are the days at the beginning of the seasons ordered by
the Church as days of fast and abstinence. They were definitely
arranged and prescribed for the entire Church by Pope Gregory VII
(1073-1085) for the Wednesday, Friday, and Saturday after 13
December (S. Lucia), after Ash Wednesday, after Whitsunday, and
after 14 September (Exaltation of the Cross). The purpose of their
introduction, besides the general one intended by all prayer and
fasting, was to thank God for the gifts of nature, to teach men to
make use of them in moderation, and to assist the needy. The
immediate occasion was the practice of the heathens of Rome. The
Romans were originally given to agriculture, and their native gods
belonged to the same class. At the beginning of the time for seeding
and harvesting religious ceremonies were performed to implore the
help of their deities: in June for a bountiful harvest, in September
for a rich vintage, and in December for the seeding; hence their
feriae sementivae, feriae messis, and feri vindimiales. The Church,
when converting heathen nations, has always tried to sanctify any
practices which could be utilized for a good purpose. At first the
Church in Rome had fasts in June, September, and December; the
exact days were not fixed but were announced by the priests. The
“Liber Pontificalis” ascribes to Pope Callistus (217-222) a law
ordering the fast, but probably it is older. Leo the Great (440-461)
considers it an Apostolic institution. When the fourth season was
added cannot be ascertained, but Gelasius (492-496) speaks of all
four. This pope also permitted the conferring of priesthood and
deaconship on the Saturdays of ember week–these were formerly
given only at Easter. Before Gelasius the ember days were known
only in Rome, but after his time their observance spread. They were
brought into England by St. Augustine; into Gaul and Germany by
the Carlovingians. Spain adopted them with the Roman Liturgy in
the eleventh century. They were introduced by St. Charles
Borromeo into Milan.