Synaxis of the Archangel Gabriel
The Synaxis of the Archangel Gabriel is celebrated on the day after the Annunciation, and a second time on July 13. It was instituted in the ninth century, perhaps to celebrate the dedication of a church at Constantinople. Originally, the Feast was observed on October 16 (Juan Mateos, Le Typikon De La Grande Eglise).
An account of the Holy Archangel Gabriel is found under March 26 and November 8.