An American atheist turned Baptist minister and Christian humanitarian leader has once again undertaken his avowed mission to feed and bring cheer to Christian children and their families in U.N. refugee camps in the Middle East.

William J. Murray, chairman of the Washington D.C.-based Religious Freedom Coalition, said he is motivated to bring aid and smiles to the faces of Christian families in the Middle East, particularly those in Syria and Iraq, since they are the most persecuted group in the world today, WND reported.

He directs the annual Christmas for Refugees programme, which he established in 2013 to make the holiday season a little brighter for the beleaguered Christians from war-torn countries in the Middle East.

Murray, 69, said he initiated the programme because Islamic-run charities in Jordan and Lebanon mostly ignore Christian refugees, preferring to help Muslim refugees only.

Murray's transformation into a devout Christian committed to doing humanitarian work is another story in itself.

"Sadly, I was raised in a Marxist home by a mother who had as much hatred for Christianity as does the leader of the Islamic State today," Murray told WND in an interview. "Just as the liberals of this day, she preached that Christianity is at the root of all evil and all wars, and that its elimination would bring about peace and the end to capitalism."

Murray said he grew up influenced by the beliefs of his mother, who was the founder of American Atheists.

However, he had a sudden spiritual transformation in 1980 when he uprooted himself from his family's atheist roots and became a Christian.

Without saying how this transformation came about, he said he simply found motivation to fight for the rights of Christians in America and persecuted Christians worldwide.

In the early 1980s he became the director of Freedom's Friends, an organisation that extended aid to victims of communism worldwide.

In the 1990s he founded the first commercial Bible publishing company in the Soviet Union. For years he organised evangelistic tours to that country.

This December, he held a number of Christmas dinner events for Christian refugee children in the Middle East, risking his life in doing so since some of the places he visited were partially controlled by the Islamic State (ISIS).

Despite the risks to his personal safety, Murray said he reaps great personal rewards from knowing that he is helping to uplift the spirits of thousands of Christian children and their families as well.

He said the most rewarding aspect of Christmas for Refugees is the moment the children forget the horrible situation their families are in.

"At one event in Lebanon a very young girl, perhaps five years old, began to cry when she realised the event was over and she would have to board the bus back to the refugee area her family lived in," Murray shared.