Feasts.

In the yearly cycle, the greatest changes in the service occur on great feast-days and during the fasts. According to the subjects of the services, the feast-days are divided into Feasts of Our Lord, in honor of God Himself, — of the Mother of God, — and Saints’ Feasts, in honor of the holy angels and of holy men. According to the solemnity of the services, they are divided into great, medium, and lesser; according to the time of celebration, into fixed, i.e., such as return periodically on the same dates of the same month in each year, — and movable, i.e., such as occur yearly on the same days of the week, but on different dates and even in different months, following the movements of the Paschal Feast.