As the Muslim community around the world begins to celebrate the holy month of Ramada, the top Catholic leader in Iraq asked for this year’s festival to be “exceptional” in terms of renouncing fundamentalism and promoting tolerance.

“The month of Ramadan provides a privileged time for fasting, praying, repentance and changing of mentality and approaches in order to live in peace with oneself and with others,” wrote Chaldean Catholic Patriarch Raphael Louis Sako.

“It is an opportunity,” he said, “to practice compassion and charity.”

Ramadan, marked by more than one billion Muslims around the world, began at midnight on June 6, and will continue until July 7.

Held during the ninth month on the Islamic calendar, the period is celebrated because Muslims believe it’s when the Quran was revealed to mankind through the Prophet Muhammad.

Sako, who’s seen scores of his flock murdered by the Islamic terrorist group ISIS, and many more fleeing the country to escape religious persecution, published an open letter to Muslims on the website of the Chaldean Patriarchate.

“In such harsh and worrying circumstances that have troubled the country, leaving thousands killed and wounded; millions of displaced people and huge destruction, I urge you to make this month an ‘exceptional Ramadan’” he wrote, before asking Muslims to renounce “sectarianism and fundamentalism.”

The patriarch, who’s made repeated appeals for the international community to step up to guarantee the survival of Christianity in the Middle East, currently at risk in countries such as Iraq and Syria, also asked for Muslims marking this holy month to concentrate on building a “culture of reconciliation,” promoting “shared values of tolerance, neighborhood and friendship,” and endorsing “peaceful coexistence, dialogue and mutual respect.”

Sako wrote he hopes that the upcoming celebration of “Eid-al-Fitr,” the end of Ramadan, becomes a double feast: not only a religious occasion to rejoice, but also a possibility to mark “the triumph of reconciliation, and peace.”

“On this event, we extend our compliments to the Iraqi Forces, for their victory, hoping that all the Iraqi territories will be released from ISIS,” he wrote.

Sako closed his letter promising prayers from the Catholic community, hoping that the combination of prayer and fasting will “enlighten and direct the hearts of all Iraqis toward the birth of a new Iraq,” one in which all citizens are treated equally.

Government observers and refugee offices believe that the current Christian population of Iraq is close to 180,000 people, most of whom live in refugee camps in Erbil, capital of the Kurdistan region, or in nearby cities.

Before the ISIS insurgence, they were estimated in 400,000, living mostly in the Nineveh plains. However, an official census from 1987 counted 1.4 million Christians in Iraq, with a high of two million in 2003, showing the dramatic decrease in the last two decades.

The Chaldean Catholic Church is one of 23 Eastern churches in full communion with Rome, historically centered in Iraq but also encompassing parts of Syria, Turkey and Iran.