His followers adopted the custom of wearing a shamrock on his feast day.
In the 18th century the manor passed by marriage to the Courtenays, afterwards earls of Devon, and Robert de Courtenay in 1220 gave the king a palfrey to hold an annual fair at his manor of Okehampton, on the vigil and feast day of St Thomas the Apostle.
The religious vocation of Israel was no longer national but ecclesiastical or municipal, and the historical continuity of the nation was vividly realized only within the walls of Jerusalem and the courts of the Temple, in the solemn assembly and stately ceremonial of a feast day.
It is difficult to explain this phrasing in any other hypothesis than that Layamon pictured to himself Arthur's hall as open on one side, and that, on a great feast-day, owing to the number of guests, the table extended beyond the covering afforded by the roof.
The victory was won on the 10th of January, the feast-day of St Sebastian the Martyr, who became the patron saint of the new settlement and gave it his name - Sao Sebastiao do Rio de Janeiro.