First Hour

Prime, or the First Hour, is a fixed time of prayer of the traditional Divine Office (Canonical Hours), said at the first hour of daylight (approximately 6:00 a.m.), between the morning Hour of Lauds and the 9 a.m. Hour of Terce. It is part of the Christian liturgies of Eastern Christianity, but in the Latin Rite it was suppressed by the liturgical reforms following the Second Vatican Council. However, clergy who have an obligation to celebrate the Liturgy of the Hours may still fulfil their obligation by using the Roman Breviary promulgated by Pope John XXIII in 1962, which contains the Hour of Prime. Like all the liturgical hours, except the Office of Readings, it consists primarily of Psalms. It is one of the Little Hours.

The word "Prime" comes from Latin and refers to the first hour of daylight (i.e., dawn). Originally, in the West, Prime was called matitutina (hora), "morning hour". Later, in order to distinguish it from the nocturnal offices of Matins and Lauds, and to include it among hours of the day, it was called prima. The name is first met with in the Rule of St. Benedict. In the Antiphonary of Bangor it is called secunda.

In the Eastern liturgies, the names for this office in the various languages also mean "first (hour)", based upon the traditional methods of calculating the hour of the day. In Ancient Rome, the period of daylight was divided into 12 hours, but the length of each hour would change depending upon the season of the year. In the Ethiopian Orthodox Church, in some monasteries the times of the services are still calculated by the shadow of the sun to this day.

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