The book "Under the shadow of the cross and crescent" Brand R.Koena was a response to the polar opinions on Judeo-Muslim relations in the Middle Ages that existed in the historical literature.Pytayas oppose both the myth of an interfaith utopia and antimifu on continuous brutal persecution by using comparative-historical method explains why the Islamic world of the Middle Ages the world, particularly in the period from the formation of Islam to the Mamluk era was much safer for Jews than life in the northern part of Christian Europe.