Tunisian Christian convert slaughtered

Warning: The video is apparently very graphic (I haven't watched it).

Here is the description: 

A young man appears held down by masked men. His head is pulled back, with a knife to his throat. He does not struggle and appears resigned to his fate. Speaking in Arabic, the background speaker, or "narrator," chants a number of Muslim prayers and supplications, mostly condemning Christianity, which, because of the Trinity, is referred to as a polytheistic faith: "Let Allah be avenged on the polytheist apostate"; "Allah empower your religion, make it victorious against the polytheists"; "Allah, defeat the infidels at the hands of the Muslims"; "There is no god but Allah and Muhammad is his messenger." 

Then, to cries of "Allahu Akbar!"—or, "God is great!"—the man holding the knife to the apostate's throat begins to slice away, even as the victim appears calmly mouthing a prayer. It takes nearly two minutes of graphic knife-carving to sever the Christian's head, which is then held aloft to more Islamic cries and slogans of victory. 

And here is some interesting comment:

In fact, only the other day a top Egyptian Salafi leader openly stated that no Muslim has the right to apostatize, or leave Islam, based on the canonical hadiths, including Muhammad's command, "Whoever leaves his religion, kill him." Islam's most authoritative legal manuals make crystal clear that apostasy is a capital crime, punishable by death. 

The first "righteous caliph," a paragon of Muslim piety and virtue, had tens of thousands of people slaughtered—including by burning, beheading, and crucifixion—simply because they tried to break away from Islam. According to the Encyclopaedia of Islam, the most authoritative reference work on Islam in the English language, "there is unanimity that the male apostate must be put to death."