It is unusual to meet jihadists in a public place in Jordan, as they tend to steer clear of security services.
However, I met Abu Mohammed al-Maqdisi, the spiritual leader of the Jordanian Salafist jihadist movement, at a book fair in Amman.
Maqdisi, also known as Isam Mohammad Taher al-Barqawi, was once described by an American think tank as the world's most influential jihadist ideologue.
He is quoted more widely than anyone else in jihadist literature and his writings helped inspire Abu Musab al-Zarqawi, the late leader of al-Qaeda in Iraq (AQI).
Observers have therefore been following what the Palestinian-born Jordanian cleric has been saying about Islamic State (IS), which grew out of AQI and has seized large parts of Iraq and Syria.