On 11 September, the Orthodox and Greek Catholics who follow the Julian Calendar commemorate the beheading of John the Baptist. The faithful keep a strict fast on that day.
According to tradition, the disciples of John the Baptist began to remember the day of the beheading of John the Baptist. But the tradition of the holy day and its spread was fully
formed in the 5th century.
In particular, the holy day is mentioned in the Armenian translation of the lectionary, which reflects the practice of the Jerusalem divine service in the 5th century.