An All-Night Vigil (Greek: αγρυπνία - agrypnia, "without sleeping"; Slavonic: Vsenoshnoe Bdenie) is a combination of multiple services whose makeup varies significantly according to regional and local tradition. In the Byzantine tradition, the service lasts through the night, consisting of the entire liturgical cycle, culminating in the Divine Liturgy. In Slavic tradition, it does not last all night but normally includes Vespers (or Great Compline), Matins and the First Hour, and it is the standard Saturday evening service. When the Vigil is celebrated, the particular rubrics for its constituent services are altered.
One of the unique characteristics of the Vigil is that Small Vespers (different from both Daily and Great Vespers) is served earlier in the evening (usually this service is only done in cathedrals and monasteries, however). This practice originated so that the monks could observe a shorter form of vespers at the canonical time (sunset), have their evening meal, and then later begin the All-Night Vigil (which includes the fuller form of Vespers). Additionally, the inclusion of the Litia and Artoklasia has as its purpose the sustenance of the faithful as they attend a service which may last eight or more hours through the night, when done in the full traditional manner.
In Byzantine practice, the All-Night Vigil includes Great Vespers including Litia and Artoklasia, Orthros, the First Hour, Third Hour, and Sixth Hour, followed by the Divine Liturgy. If the Divine Liturgy is celebrated immediately, the First through Sixth Hours may be omitted.
Because of its great length, the All-Night Vigil is rarely celebrated in parishes, but it is done in some places, especially for major feast days. It is commonly celebrated in monasteries, however, especially for the Great Feasts and the patronal feast of the community.
In Russian practice, the All-Night Vigil is the standard Saturday evening service and usually consists of Vespers, Matins, and the First Hour—though on certain feasts, it includes Great Compline instead of Vespers. In parishes, Vigils are less strenuous than those conducted in the monasteries, but the structure remains the same. The Vespers often contains a Litia with the blessing of the bread—this is always the case on Great Feasts.
The differences between the more rigorous practice and general parish practice are that the latter contains some abbreviations, while the former is usually chanted to slower melodies and also includes additional readings that are done at certain places in the service. A less rigorous practice is to stop the Vigil after the First Hour, then to resume with the Third and Sixth Hours the following morning, followed immediately by the liturgy. In the more rigorous practice, the Hours continue without such a break.