Today, July 13th, is the Synaxis of the Archangel Gabriel. It is thought that the date was transferred to this day from March 26 so that it could be celebrated more festively than in the period of the Great Fast. All the miracles of the Archangel are celebrated on this feast day, which has been listed here in the church books since the ninth century.
A synaxis means gathering, assembly, reunion. It is exactly equivalent to theLatin collecta (from colligere), and corresponds to synagogue (synagoge), the place of reunion. We use that term for the Archangel’s holiday because it is a reunion of his memory for festive purposes. Chronia Polla Gabriel.
You can read more about the Archangel here.