A small cardboard box sits on the corner of Father Thabet's desk in Erbil, with four simple words written on it in three languages.

It reads 'coin of the widow', in reference to a story told in the Gospel of Mark about an elderly woman who had very little money, but still gave it all to the temple treasury.

The priest is encouraging Christians who have fled extreme violence and persecution at the hands of Islamic State to live generously despite their troubles, and help one another.

He ministers to his congregation from Karamles – a village overrun by ISIS in 2014 – in their temporary home in a complex for internally displaced people in Erbil.

"I ask my people to put something in this box. Even if it is just a small coin, whatever they can spare to help people who even poorer than they," Thabet told persecution charity Open Doors.

"Even when you have almost nothing to spend, still you can help others. That is how we keep the hope alive; that is how we spread the hope."

About a third of the Christians from Karamles, an ancient Assyrian village less than 18km from Mosul, have fled Iraq since 2014.

However, Thabet said many more want to stay in the country, and it's his job to "inspire and mobilise people, to help them rebuild their trust in their neighbours and their position in society".

Karamles was liberated as part of the offence to retake Mosul that began on October 17.

Thabet has since returned to the village to raise a cross covered with flowers on an overlooking hill.

"I am so happy I can do this. I'm smiling from cheek to cheek and I weep tears of joy at the same time," he said at the time, according to World Watch Monitor. "This is the trip I have been praying for, for two years now."

"My dream is to bring all the Christians back to this village. Then we will worship outside on Barbara Hill; we will have the Eucharist in the open air," he added. "Everybody will see that this is the Church; this is the Body of Christ; this is Christian land. That is my dream – to give a testimony to the world."

The church in Karamles has been badly damaged by ISIS, but is repairable.