This is no surprise. Nor are father and son “extremists.” Islam mandates death for non-Muslim subjects of the Islamic state who mention “something impermissible about Allah, the Prophet (Allah bless him and give him peace), or Islam” (‘Umdat al-Salik, o11.10), and such laws are based upon passages in the Hadith and Sira in which Muhammad orders the murders of people who have insulted him.
These include Abu Afak, who was over one hundred years old, and the poetess Asma bint Marwan. Abu Afak was killed in his sleep, in response to Muhammad’s question, “Who will avenge me on this scoundrel?” Similarly, Muhammad on another occasion cried out, “Will no one rid me of this daughter of Marwan?” One of his followers, Umayr ibn Adi, went to her house that night, where he found her sleeping next to her children. The youngest, a nursing babe, was in her arms. But that didn’t stop Umayr from murdering her and the baby as well. Muhammad commended him: “You have done a great service to Allah and His Messenger, Umayr!” (Ibn Ishaq, 674-676).
Then there was Ka’b bin Al-Ashraf. Muhammad asked: “Who is willing to kill Ka’b bin Al-Ashraf who has hurt Allah and His Apostle?” One of the Muslims, Muhammad bin Maslama answered, “O Allah’s Apostle! Would you like that I kill him?” When Muhammad said that he would, Muhammad bin Maslama said, “Then allow me to say a (false) thing (i.e. to deceive Kab).” Muhammad responded: “You may say it.” Muhammad bin Maslama duly lied to Ka’b, luring him into his trap, and murdered him. (Sahih Bukhari, volume 5, book 59, number 369)
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