For more than a month, al-Kasasbeh's family, hailing from a high-ranking tribe considered especially loyal to Jordan's royal family, implored ISIS to let him go.
Hope that he could be spared ended in early February when a video emerged showing the 29-year-old pilot in a cage, being burned alive.
To Zakaria, Abdullah reiterated his commitment to stop ISIS. He called its fighters "outlaws" who twist Islam and use "intimidation" as their biggest weapon.
The King told Zakaria that he didn't watch the video of the pilot's slaying.
"I -- many of us refused to see what I think is propaganda," Abdullah said.
He felt "disgust, sadness for the family" and his "heart went out to the father, the mother, the brothers, the sisters," the King continued. "His wife, they'd only been married for five months. (I felt) anger as the son of the Arab army, Jordanian armed forces. God bless his soul. He's a brother in arms.
"All soldiers past and present were disgusted by the brutality of what Moath was put through," Abdullah said.
A tiger by the tail
During his interview with Zakaria, the King repeatedly referred to ISIS, the Islamic State of Iraq and Syria, as Daesh
. That's an acronym for al-Dawla al-Islamiya al-Iraq al-Sham.
Many in the Middle East prefer to use Daesh because, to them, the acronym ISIS suggests the terror group is a legitimate state. They refuse to give the militants that much credit.
"I think if ISIS, or Daesh as we call them, try to intimidate Jordanians ... just (has) the reverse effect," Abdullah said. "If you look at our history, we're a country that's used to being outgunned and outnumbered. We've always punched way above our weight. I think, if anything, Daesh has us as a tiger by the tail."
The pilot's killing "just motivated Jordanians to rally around the flag," he said. "The gloves have come off."
ISIS is "always trying to intimidate, scare, put fear in people's hearts," the King told Zakaria. "They are trying to invent falsely a linkage to a caliphate, link to our history in Islam that has no truth or bearing to our history."
ISIS is recruiting "deluded young men and women" who "think this is an Islamic nation."
U.S. President Barack Obama has caught flak for saying he didn't want to refer to ISIS members as Islamic extremists because their actions are not Islamic.
"I think he is right," Abdullah said. "This is something that has to be understood on a much larger platform. (ISIS) is looking for legitimacy (that) they have inside of Islam."
"I'm a Muslim," the King said. "These people (ISIS members) ... are on the fringe of Islam."
"The barbarity with the way they executed our brave hero (the pilot), I think, shocked the Muslim world, especially Jordanians and people from this region," Abdullah said.
Is Jordan's response really 'earth-shattering'?
In the wake of the pilot's death, a Jordanian government spokesman vowed an "earthshaking retaliation."
Zakaria asked Abdullah if Jordan's action has lived up to that fiery rhetoric.
"Earth-shattering from all military capabilities is not something that happens overnight," he answered, saying that airstrikes have continued. "There are continued operations going on in Syria. We are coordinating with our friends in Iraq."
He said there is a "long-term approach" to fighting ISIS but didn't give any more details.
The war against ISIS is as much Jordan's war as that of any other country in the coalition, he said.
"It is our war. It has been for a long time," he said. "These are outlaws, in a way, of Islam, the minute they set up this irresponsible caliphate to try to expand their dominion over Muslims."
ISIS cannot argue that Jordan and other Muslim nations should not attack them because they're fellow Muslims, he said.
The militants "try to make themselves look as victims," he said. "What about the hundreds if not thousands of Muslims they have killed in Syria and Iraq over the past year and a half?"
Jordan has a "responsibility to reach out to eastern Syria" and to western Iraq where people have been "executed in large numbers" by ISIS, Abdullah insisted.
"So this is our war," he said. "We have a moral responsibility to reach out to those Muslims to protect them and stop (ISIS) before they reach our border."
What about al-Assad?
Zakaria asked Abdullah what he thinks about the perception some have that Syrian President Bashar al-Assad
is interested in combating ISIS, meaning al-Assad and Abdullah have common enemies.
ISIS has gained strength by exploiting the unrest in Syria during its ongoing civil war
. That war is the result of unrest in Syria that originally started in 2011 within the context of the Arab Spring, protests for democracy or changes in government that raged in parts of the Middle East and North Africa in 2010 and 2011.
Syrian protesters, in 2011, wanted to bring change to the government which they said stifled expression in the harshest ways.
The al-Assad regime violently cracked down on the demonstrators, chaos erupted throughout Syria, and eventually many on the international stage came to believe al-Assad should go.
The King told Zakaria that the "history of dealing with" the al-Assad regime and the "history of dealing with" ISIS are two separate things.
"What has taken prominence at the moment is ISIS, Daesh," he said.
Abdullah rhetorically asked whether both issues can be dealt with at the same time. "This has to be decided by the international community," he said. "We believe there has to be a political solution" in Syria, and that has "not been clarified at the moment."