Returning from his trip to Asia, President Obama issued a statement reacting to the beheading of U.S. aid worker Peter Kassig by Islamic State (ISIS/ISIL) terrorists.

Kassig, a convert to Islam, took the name Abdul-Rahman and was captured and held hostage by members of ISIS a year ago.

“ISIL’s actions represent no faith, least of all the Muslim faith which Abdul-Rahman adopted as his own,” Obama wrote. “Today we grieve together, yet we also recall that the indomitable spirit of goodness and perseverance that burned so brightly in Abdul-Rahman Kassig, and which binds humanity together, ultimately is the light that will prevail over the darkness of ISIL.”

Obama called the action “an act of pure evil by a terrorist group that the world rightly associates with inhumanity.”