This week, Orthodox Christians celebrate Holy Week, leading up to Easter on Sunday.
The date has been observed differently in the Western Churches, the Eastern Orthodox and Coptic Churches for centuries.
It is calculated using the Sun and Moon and is on the first Sunday after the Paschal Full Moon. It changes each year according to the Julian calendar used by Eastern Churches and the Gregorian calendar used in the West, and only occasionally falls on the same date for both Churches.
This year, Easter was celebrated in the West on March 27. It will be celebrated on the 1 May in Eastern Churches.
Below are eight stunning pictures of celebrations in Jerusalem.
Greek Orthodox Patriarch of Jerusalem Metropolitan Theophilos blesses the crowd during the Washing of the Feet ceremony.
An Ultra-Orthodox Jewish boy holds a Torah scroll during a special priestly blessing for Passover at the Western Wall, Judaism's holiest prayer site in Jerusalem's Old City.
Members of the Greek Orthodox clergy outside the Church of the Holy Sepulchre.
Patriarch Theophilos (C) leads the ceremony.
Patriarch Theophilos washes the foot of a priest.
Clergy and Orthodox Christians outside the church.
Onlookers watch from above.
