Memorial of St. Callistus I, Pope and Martyr: Invitatory
Invitatory Antiphon: Come, let is worship Christ, the King of martyrs.
Presentation of the Liturgy of the Hours (Divine Office) from The Liturgy of the Hours (Four Volumes) © 1975, International Commission on English in the Liturgy Corporation. The texts of Biblical readings are reproduced from the New American Bible © 1975