Now I caught that he was sporting a salafi beard, with the tell-tale feature being no mustache, but maybe it was due to the lighting or not seeing a close up picture of his forehead. The guy is in fact sporting a zebibah on his forehead.
The Daily Mail says he was possibly in the process of converting to islam. This looks more like he was the leader of a jihad cell to me.
Friends of Boyle’s previously said Boyle had an ‘academic interest’ in terrorism and may have been converting to Islam when he was captured.
The bruise on the forehead, called a “Zebiba”. It is an ostentatious show of crypto-piety, caused by deliberately banging one’s forehead onto a hard floor while doing Islamic ritual, for no other reason than to cause a bruise in the skull so others will know you banged your head into the floor while doing Islamic ritual.
Somewhat like street prayers, but it leaves a more lasting mark.