A lection, also called the lesson, is a reading from scripture in liturgy. In many Christian denominations, the readings of the day are appointed in the lectionary.
A Scripture lesson being read in a service of Nine Lessons and Carols.
A lectionary 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.
Page from the 11th century "Bamberg Apocalypse", Gospel lectionary. Large decorated initial "C". Text from Matthew 1:18–21 (Bamberg State Library, Msc.Bibl.140).
Portrait of Rembrandt's mother reading a lectionary, c. 1630 (Rijksmuseum, Amsterdam). The painting has more recently been attributed to Gerrit Dou.
A German Roman Catholic lectionary for year C on an ambo after Mass
Jaharis Byzantine Lectionary, Metropolitan Museum of Art