His holy relics are kept in the Cathedral of Thessalonica. A full service was composed for his feast day by the Patriarch Philotheus in 1368, when it was established that his feast be celebrated on this day. Since works without right faith avail nothing, we set Orthodoxy of faith as the foundation of all that we accomplish during the Fast, by celebrating the Triumph of Orthodoxy the Sunday before, and the great defender of the teachings of the holy Fathers today.
Resurrectional Apolytikion in the Second ToneWhen You descended unto death, O Lord who yourself are immortal Life, then did You mortify Hades by the lightning flash of Your Divinity. Also when You raised the dead from the netherworld, all the Powers of the heavens were crying out: O Giver of life, Christ our God, glory be to You.
Apolytikion in the Plagal of the Fourth ToneO Gregory the Miracle Worker, light of Orthodoxy, support and teacher of the Church, comeliness of Monastics, invincible defender of theologians, the pride of Thessalonica, and preacher of grace, intercede forever that our souls may be saved.
Seasonal Kontakion in the Plagal of the Fourth ToneTo you, Theotokos, invincible Defender, having been delivered from peril, I, your city, dedicate the victory festival as a thank offering. In your irresistible might, keep me safe from all trials, that I may call out to you: "Hail, unwedded bride!"