A U.S. federal court passed a 40 year prison sentence on a former missionary from Oklahoma for molesting children at a Kenyan orphanage. Twenty-one-year-old, Matthew Lane Durham, was accused of molesting eight children at the Upendo Children’s Home in Nairobi, Kenya in 2014.

Although Durham claimed he did not molest the children, prosecutors revealed he told staff members at the children’s home that he had been possessed by an “evil spirit.” He also claims he doesn’t remember the crimes.

During a preliminary hearing, prosecutors revealed that a live-in caretaker at the orphanage said the children reported that Durham either touched them sexually or encouraged them to touch themselves while he watched. According to a criminal affidavit, Durham was confronted by the founder of Upendo along with several church members, where he allegedly confessed to his crimes.

Despite pleading not guilty to 17 charges last June, a federal judge found Durham guilty on seven counts, including engaging in illicit sexual conduct in foreign places. However he was acquitted on three of the counts by US District Judge David Russell in January because the judge felt prosecutors failed to establish enough evidence that Durham had engaged in sexual acts with with one of the victims.

Prosecutors argued Durham used his position as a missionary to win the trust of the children in order to prey on them. But Durham’s attorney claimed his handwritten and taped confessions were coerced. Officials at the children’s home only reported Durham to the authorities after sending him home to the United States.

According to records released by the U.S. Attorney for the Western District of Oklahoma, Durham volunteered at the orphanage, which helps care for neglected and disabled children. In the affidavit, Durham engaged in sexual acts with multiple children, male and female, aged between 4 and 10 years, from April to June of 2014.

In an Oklahoma court on Monday, Durham said, “Judgment from God is central, not the judgment of man, I do not fear God’s judgment.”

On Monday, Judge David Russell called Durham a serial rapist and “kids’ worst nightmare.” In addition to 40 years of jail time, Durham was also fined $15,863.