"Today, the entire world is appalled by the brutal murder of Jim Foley by the terrorist group, ISI. Jim was a journalist, a son, a brother, and a friend. He reported from difficult and dangerous places, bearing witness to the lives of people a world away," Obama told mediapersons at Martha's Vineyard, where he is spending his two-week summer vacation.
Foley was taken hostage nearly two years ago in Syria, and he was courageously reporting at the time on the conflict there, he said.
"Jim was taken from us in an act of violence that shocked the conscience of the entire world. He was 40 years old. One of five siblings, the son of a mom and dad who worked tirelessly for his release," he added.
Obama said, ISIS which over the past several months has unleashed a wave of violence and brutal murder of not only Muslims but also religious minorities, speaks for no language.
"Their victims are overwhelmingly Muslim, and no faith teaches people to massacre innocents. No just God would stand for what they did yesterday and what they do every single day.
"ISIS has no ideology of any value to human beings. Their ideology is bankrupt," Obama said. "They may claim, out of expediency, that they are at war with the US or the West, but the fact is, they terrorise their neighbours and offer them nothing but an endless slavery to their empty vision and the collapse of any definition of civilised behavior," he said. "And people like this ultimately fail."
Asserting that a group such as ISIS has no place in the 21st century, Obama said the US will continue to do what it must do to protect its people.
"We will be vigilant and we will be relentless. When people harm Americans, anywhere, we do what is necessary to see that justice is done," he said. "We act against ISIS standing alongside others. The people of Iraq who, with our support, are taking the fight to the ISIS, must continue coming together to expel these terrorists from their communities.
"The people of Syria, whose story Jim Foley told, do not deserve to live under the shadow of a tyrant or terrorists. They have our support in their pursuit of a future rooted in dignity," Obama said.