Octave of Easter

The term Octave of Easter may refer either to the eight-day period (Octave) in Eastertide that starts on Easter Sunday and runs until the Sunday following Easter, inclusive; or it may refer only to that Sunday after Easter, the Octave Day of Easter (often known as Low Sunday, particularly in the Anglican Communion). That Sunday is also known historically as St. Thomas Sunday (especially among Eastern Christians), Quasimodo Sunday and Quasimodogeniti. Since 1970 Low Sunday has been officially known as the Second Sunday of Easter (referring to the Easter season) in the Roman Catholic Church. On 30 April 2000, it was also designated as Divine Mercy Sunday by Pope John Paul II.

The Octave of a feast refers to an eight-day festal period commencing with that feast. Presently in the Roman Catholic Church, Easter is one of only two solemnities that carries an octave, the second being Christmas Day, although until recently many feasts had octaves.

The name Quasimodo came from the Latin text of the traditional Introit for this day, which begins "Quasi modo geniti infantes..." from 1 Peter 2:2, roughly translated as "As newborn babes desire the rational milk without guile...". Literally, quasi modo means "as if in [this] manner".

On the Octave Day of Easter, called Saint Thomas Sunday in the East, the Gospel reading is always John 20:19-29, relating the appearance of Christ to his disciples, with Thomas the Apostle present, on the Sunday following his resurrection. A traditional name in English is Low Sunday, perhaps given this name because of the contrast with the high festival of Easter on the preceding Sunday, or the word "Low" may be a corruption of Latin Laudes, the first word of a sequence in use in the Sarum Rite. Another name is Quasimodo Sunday, from the first words of the introit in Latin.

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