AMMAN, Jordan — There was one sentiment that many of the Middle East’s competing clerics, fractious ethnic groups and warring sects could agree on Wednesday: a shared sense of revulsion at the Islamic State’s latest atrocity, burning alive a Jordanian pilot inside a cage.

In Syria, the government denounced the group that has been fighting it for months, but so did Qaeda fighters who oppose both the government and the Islamic State. In Egypt, the Muslim Brotherhood and the Egyptian government for once agreed on something, the barbarity of the militant group for the way it murdered the Jordanian, First Lt. Moaz al-Kasasbeh. And in Cairo, Grand Imam Ahmed al-Tayeb, the head of the 1,000-year-old Al Azhar institute, was so angered that he called for the Islamic State’s extremists to be “killed, or crucified, or their hands and legs cut off.”

That leading Sunni scholar’s denunciation was even harsher than similar outbursts from the region’s Shiite leaders, theologically the more traditional foes of the Islamic State.

In a way that recent beheadings of hostages had not, the immolation of Lieutenant Kasasbeh set off a regionwide explosion of anger and disgust at the extremists, also known as ISIS or ISIL, or to most Arabs by the word “Daesh.” Even more significant, in a chronically embattled region that bequeathed to the world the expression, “The enemy of my enemy is my friend,” the Islamic State suddenly found itself friendless in the extreme.