Trinity Sunday

Trinity Sunday, the Sunday immediately following Whitsunday, so called as being set aside for the special honour of the Blessed Trinity. The festival was not generally observed before the 12th century, though kept in Liège two centuries earlier; only in 1334 was it established by Pope John XXII. as a common festival of the whole Western Church. The mass and office peculiar to the day, however, are of greater antiquity.