The Koran reveals many of the core beliefs of Islam. The Koran says that Allah, the god of the Muslims, is merciful to those who believe, and that he is their protector. But, the unbelievers have no protector. He is the only god, and no other gods exist except for Allah. In Surah 47 of the Koran, there are many references to the Garden, the place where righteous Muslims go when they die. The place where the unbelievers go is called The Fire.
In Surah 47:5, it says:
And when you meet in regular battle those who disbelieve, smite their necks; and, when you have overcome them, by causing great slaughter among them, bind fast the fetters – then afterwards either release them as a favour or by taking ransom – until the war lays down its burdens. That is the ordinance. And if ALLAH had so pleased, HE could have punished them Himself, but HE has willed that HE may try some of you by others. And those who are killed in the way of ALLAH – HE will never render their works vain.
Muslims are called to subdue unbelievers when they meet with them in battle and then subdue them by slaughtering them. It says that Allah can destroy the unbelievers himself, he wants to test his followers. It also says that Allah will not render the works of faithful Muslims in vain. This was one of the reasons for the conquests of Muhammad and his successors.
The historian Procopius wrote a work called The Secret History as a strong critique of the Byzantine emperor Justinian the great. He said that Justinian was a liar, and oppressor, and a persecutor of whoever did not agree with him. Procopius even compared him the emperor Domitian, who was known for his bloodthirstiness and persecution of Christians. Justinian was also portrayed as a robber, who looted the houses of the rich and then wasted the money he received on extravagance and foolish bribes to the barbarians. He even accused Justinian of influencing the barbarians to attack his own citizens. Procopius said that it was possible that he had murdered more people than had ever been murdered before. Procopius was an effective writer and used sarcasm and rhetoric when describing Justinian and his actions.