OKLAHOMA CITY – A federal judge sentenced a former missionary from Oklahoma to 40 years in prison for sexually abusing children at an orphanage in Kenya.

Matthew Durham, 21, was found guilty on seven counts of engaging in illicit sexual conduct in foreign places in June 2015. The allegations involve six girls and a boy at an orphanage where Durham spent time in 2014.

During the trial, prosecutors submitted a taped confession from Durham, who admitted to raping some of the girls and admitted to more sexual abuse in handwritten notes.

Five of the alleged victims testified against Durham in the trial, and the courtroom was sealed during the testimony.

During the case, Durham testified he had a demon inside him named “Luke,” who made him “do horrible things.”

Three months after the trial, a judge acquitted Durham on three of the counts he was convicted of, saying, “the government failed to establish that Defendant engaged in a sexual act with the victim alleged in those counts.”

Durham faced sentencing for the four counts against him on Monday.

A woman who read the victim impact statements said many of the children have nightmares and still live in fear of Durham.

During sentencing, the prosecution called Durham a serial rapist, a molester and a sexual predator without a conscience.

Durham spoke to the courtroom saying, “all I wanted was to follow God’s plan for me.”

He told the court he would “do my best while incarcerated.”

“Judgement of God is central, not the judgement of man. I do not fear God’s judgement,” he said in court.

He ended his statement asking the court for mercy.

The judge said the violent acts Durham committed demand a harsh sentence.

He added that Durham was the children’s “worst nightmare come true.”

The former missionary was sentenced to serve 40 years in prison for four counts of engaging in illicit sexual conduct in foreign places.

“Mr. Durham took advantage of his position as a ministry volunteer to sexually assault multiple children in Kenya,” said Acting U.S. Attorney Mark Yancey.  “The significant sentence imposed today will remove the threat of any other children being exploited by him.   However, the innocence of the child victims cannot be restored and their lives will never be the same.  It is our hope and prayer that his conviction and lengthy sentence will someday bring them some comfort and peace.”

Prosecutors alleged Durham targeted orphans while volunteering at the Upendo Children’s Home in Nairobi between April and June 2014.

The four counts Durham was convicted of involved three girls and a boy ranging in age from 5 to 14.

Durham was also ordered to pay restitution in the amount of $15,863.23 for the cost it took to bring the victims and witnesses to Oklahoma to testify.