During this chanting the senior priest and deacon perform a full censing of the church.
In Greek practice, the megalynarion is a short hymn for the saint of the day or the feast that is sung after "Among the first..." at the Divine Liturgy.
In both the Greek and Slavic traditions the term Megalynarion also describes a hymn chanted on Great Feasts in place of the usual Axion Estin following the Epiclesis of the Liturgy.
Normally, this Megalynarion consists of the refrain and Irmos of the Ninth Ode of the Canon of the feast which was chanted at Matins.
St. Cosmas the Melodist (or Hymnographer), who wrote the original megalynarion to the Theotokos (Virgin Mary), "More honorable than the Cherubim..." for the 9th Ode of the Canon of Great and Holy Thursday.