A lectionary (Latin: lectionarium) is a book or listing that contains a collection of scripture readings appointed for Christian or Jewish worship on a given day or occasion. There are sub-types such as a "gospel lectionary" or evangeliary, and an epistolary with the readings from the New Testament Epistles.

Both Hebrew and Christian lectionaries developed over the centuries. Typically, a lectionary will go through the scriptures in a logical pattern, and also include selections which were chosen by the religious community for their appropriateness to particular occasions. The one-year Jewish lectionary reads the entirety of the Torah within the space of a year and may have begun in the Babylonian Jewish community; the three-year Jewish lectionary seems to trace its origin to the Jewish community in and around the Holy Land.

Within Christianity, the use of pre-assigned, scheduled readings from the scriptures can be traced back to the early church, and seems to have developed out of the practices of the second temple period. The earliest documentary record of a special book of readings is a reference by Gennadius of Massilia to a work produced by Musaeus of Marseilles at the request of Bishop Venerius of Marseilles, who died in 452, though there are 3rd-century references to liturgical readers as a special role in the clergy.

Easter, also called Pascha (Aramaic, Greek, Latin) or Resurrection Sunday, is a Christian festival and cultural holiday commemorating the resurrection of Jesus from the dead, described in the New Testament as having occurred on the third day of his burial following his crucifixion by the Romans at Calvary c. 30 AD. It is the culmination of the Passion of Jesus Christ, preceded by Lent (or Great Lent), a 40-day period of fasting, prayer, and penance.

Eastertide (also known as Eastertime or the Easter season) or Paschaltide (also known as Paschaltime or the Paschal season) is a festal season in the liturgical year of Christianity that focuses on celebrating the Resurrection of Jesus Christ. Preceded by Lent, it begins on Easter Sunday, which initiates Easter Week in Western Christianity, and Bright Week in Eastern Christianity.

There are several Eastertide customs across the Christian world, including flowering the cross, sunrise services, the wearing of Easter bonnets by women, exclaiming the Paschal greeting, clipping the church, and decorating Easter eggs, a symbol of the empty tomb. Additional Eastertide traditions include egg hunting, eating special Easter foods and watching Easter parades. The Easter lily, a symbol of the resurrection in Christianity, traditionally decorates the chancel area of churches on this day and for the rest of Eastertide.

When the Anglican and Lutheran churches implemented their own calendar and lectionary reforms in 1976, they adopted the same shortened definition of the Easter season as the Roman Catholic Church had promulgated six years earlier. In the Church of England, the Easter season begins with the Easter Vigil and ends after Evening Prayer (or Night Prayer) on the Day of Pentecost. Some Anglican provinces continue to label the Sundays between Easter and the Ascension "Sundays After Easter" rather than "Sundays of Easter"; others, such as the Church of England and ECUSA, use the term "Sundays of Easter".