It’s the feast of St. Mark. Celebrate with the Christians of Alexandria, the Church founded and ruled by St. Mark. The Egyptian liturgy, of course, was named after Mark, and the Patriarchs (Popes) of Alexandria consider themselves his successors. St. Jerome counts Mark among his Illustrious Men:
Mark the disciple and interpreter of Peter wrote a short gospel at the request of the brethren at Rome embodying what he had heard Peter tell. When Peter had heard this, he approved it and published it to the churches to be read by his authority, as Clement in the sixth book of his Hypotyposes and Papias, bishop of Hierapolis, record. Peter also mentions this Mark in his first epistle, figuratively indicating Rome under the name of Babylon: “She who is in Babylon elect together with you salutes you and so does Mark my son.” So, taking the gospel which he himself composed, he went to Egypt and first preaching Christ at Alexandria he formed a church so admirable in doctrine and continence of living that he constrained all followers of Christ to his example. Philo, most learned of the Jews, seeing the first church at Alexandria still Jewish in a degree, wrote a book on their manner of life as something creditable to his nation telling how, as Luke says, the believers had all things in common at Jerusalem, so he recorded that he saw was done at Alexandria, under the learned Mark. He died in the eighth year of Nero and was buried at Alexandria, Annianus succeeding him.