Following last week's online release of an audio message from the caliph of the Islamic State, one expert says the group's understanding of Islam calls on all Muslims to re-evaluate Islamic history.

"The only solution is a radical reform to the internal reading of Islamic history," Fr. Samir Khalil Samir, an Egyptian-born Jesuit and acting rector of the Pontifical Oriental Institute, wrote May 15 at AsiaNews.

A day prior, the Islamic State had released a recording of its leader, Abu Bakr al-Baghdadi, saying, "There is no excuse for any Muslim not to migrate to the Islamic State … joining (its fight) is a duty on every Muslim. We are calling on you either to join or carry weapons (to fight) wherever you are."

The recording also says that "Islam was never a religion of peace. Islam is the religion of fighting. No-one should believe that the war that we are waging is the war of the Islamic State. It is the war of all Muslims, but the Islamic State is spearheading it. It is the war of Muslims against infidels."

Fr. Samir said al-Baghdadi's message is "very shrewd because it corresponds to the expectations of a part of the Islamic world," and that Salafis – followers of a movement that takes the first generations of Islamic society as the model – "will be happy about it and will say: Finally, we find the true Islam!"

The word al Baghdadi used for migration, hijra, is of significance, according to Fr. Samir. The hijra was the migration of Muhammad and his followers from Mecca to Medina in 622, which "represents the transition from a peaceful Islam to a bellicose Islam."

Fr. Samir recounted that Muhammad was nonviolent in Mecca, but after a year in Medina "he began to fight, first against the Makkans, then against the tribes, in order to convert them…Most tribes in Arabia ended up following him. However, they did so because he was a military chief not a religious leader."

The Jesuit backs up this claim by noting that when Muhammad died, tribes across the Arabian peninsula rebelled against his successor, Abu Bakr, the first caliph, in the Ridda wars. Abu Bakr consolidated the caliphate, and expanded it into modern-day Iraq and Jordan.

"It is interesting," Fr. Samir wrote, "that this new 'caliph' chose Abu Bakr as his name and that he wants to launch a holy war around the world, to subjugate everyone to Islam."

al Baghdadi's message, he charged, "is meant to rekindle an idea that is deeply embedded in Islam, namely: let us all go through our hijrah, let us leave behind all those who want an Islam of peace, and let us move to the true Islam that conquered Arabia first, then the Middle East, then the Mediterranean."

The Islamic State emerged amid the Syrian civil war, and expanded into Iraq in 2014, conquering sizable portions of both countries and declaring a caliphate. Last month, the caliphate was pushed out of the Iraqi city of Tikrit, though it seized Ramadi May 17, and is currently closing in on Palmyra, one of the Middle East's greatest archaeological sites.

Fr. Samir considers the caliph's message an appeal to young Muslims who are committed to their religion, and said it "will convince many Muslim traditionalists to become Salafis and fight."

"Faced with such call to arms, what can be done?" the priest asked. Amid the Islamic State's war "a military fight might be necessary, but it will not be decisive."

"Military actions will reduce the violence, shed less blood, push back IS, but the movement will continue because it is part of Islam."

Fr. Samir wrote that "the only solution is a radical reform to the internal reading of Islamic history."

He writes that al-Baghdadi's claim that "Islam was never a religion of peace" is an exaggeration, and that the religion has "also had periods of peace. To say that Islam is only war is also a mistake."

"Islam is both war and peace," Fr. Samir reflected. "And it is high time for Muslims to re-examine their history."