According to the 1962 Missal of St. John XXIII the Extraordinary Form of the Roman Rite, today is the feast of St. Ancetus, who was the tenth successor of St. Peter. He governed the Church from 155 to 166, years of great difficulty when Christianity in Rome had to face not only persecution by the emperors but also the heretical tendencies of the second century. St. Anicetus was visited in Rome by St. Polycarp, Bishop of Smyrna, who came to discuss with him the date of Easter.