The option for the poor or the preferential option for the poor is one of the basic principles of the Catholic Social Teaching traition. The phrase option for the poor was used by Fr Pedro Arrupe, S.J. in 1968 in a letter to the Jesuits of Latin America. As a developed theological principle it was first articulated by Fr. Gustavo Gutierrez, O.P. in his landmark theological book, A Theology of Liberation, the principle is rooted in both the Old and New Testaments and claims that a preferential concern for the physical and spiritual welfare of the poor is an essential element of the Gospel. This principle was articulated by the Catholic Bishops of Latin America as well as by several popes, particularly Pope John Paul II.