Holy Martyr Peter of Sinope, who suffered for Christ.
Saint Peter came from Sinope on the Black Sea and, tradition relates, was put to death for his confession of Christ. The synaxaria commemorate him on the day of the Synaxis of the Twelve Apostles.
Feast day
On the New Calendar, Peter of Sinope is commemorated on June 30. Churches on the Old (Julian) Calendar keep the feast on July 13 of the civil calendar.
Also commemorated on June 30

Synaxis of the Holy Apostles
Great Feast, Σύναξις Αποστόλων
Synaxis of the Glorious and All-Praised Twelve Apostles.
Peter, Prince of the Horde
Saint, Πέτρος ο Πρίγκιπας του Ορντύνσκ
Righteous Peter, prince of the Golden Horde, who was baptised and founded a monastery at Rostov.