Major holidays for Muslims and Jews are both being marked this Saturday, for the first time since 1981. The Muslim holiday of Id al-Adha and the Jewish holiday of Yom Kippur coincide once every 33 years, as Judaism and Islam rely on lunar calendars.

Yom Kippur is Judaism's Day of Atonement, when devout Jews fast and ask God to forgive them for their transgressions, attending intense prayer services in synagogues. Businesses and airports in Israel shut down as television and radio stations go silent and highways stand empty – except for bicycle traffic in secular communities.

Muslims are marking Id al-Adha, a three-day holiday that commemorates the willingness of the prophet Ibrahim — or Abraham as he is known in the Bible — to sacrifice his son in accordance with God's will, though in the end God provides him a sheep to sacrifice instead. On the start of Id al-Adha, Muslims slaughter sheep, cattle and other livestock, and give part of the meat to the poor.



Palestinian Muslim worshipers walk past a Jewish worshiper near the al-Ibrahimi mosque, or the Tomb of the Patriarch, in Hebron October 04, 2014. Photo: AFP



Palestinian Muslim worshipers pray on October 4, 2014 at the al-Aqsa Mosque in Jerusalem on the first day of Id al-Adha. Photo: AFP



Palestinians walk near the al-Aqsa Mosque in Jerusalem following the morning Id al-Adha prayer in Jerusalem, October 4, 2014. Photo: AFP



Secular Tel Aviv residents take advantage of the empty roads on Yom Kippur to ride bicycles, October 4, 2014. Photo: Tomer Appelbaum



Tel Aviv residents on the eve of Yom Kippur, October 3, 2014. Photo: Tomer Appelbaum



Russian Muslims pray near the Central Mosque during the Id al-Adha festival in Moscow on October 4, 2014. Photo: AFP



A Crimean Tatar Muslim cuts up the carcass of a sheep on the first day of the Id al-Adha, in the city of Bakhchisaray, October 4, 2014. Photo: AFP



Afghan children on the Id al-Adha festival at the Shah-e Do Shamshira mosque in Kabul, October 4, 2014. Photo: AFP



Muslim pilgrims gather to pray at Jabal Al Rahma holy mountain, during the annual hajj pilgrimage, near Mecca, Saudi Arabia, October 3, 2014. Photo: AP



Members of An-Nadzir Muslim sect offer morning prayers, marking the Id al-Adha in Gowa, Indonesia, October 4, 2014. Photo: AP



Kosovo Muslims offer Id al-Adha prayers outside Sultan Mehmet Fatih grand mosque in the capital Pristina, Kosovo, October 4, 2014. Photo: AP



Filipino Muslims attend an early morning prayer to mark Id al-Adha at the Blue Mosque at Taguig, east of Manila, Philippines, October 4, 2014. Photo: AP



Ultra-Orthodox Jews of the Hassidic sect Vizhnitz gather on a hill overlooking the Mediterranean sea as they participate in a Tashlich ceremony in Herzliya, Israel, October 2, 2014. Photo: AP



An ultra-Orthodox Jewish man whips another during the traditional Malkot ceremony, ahead of Yom Kippur, in Beit Shemesh, Israel, October 3, 2014. Photo: AP



Jews pray ahead of Yom Kippur at the Western Wall in Jerusalem, October 2, 2014. Photo: Olivier Fitoussi