VATICAN CITY (AP) - The Vatican's leading sex crimes investigator has told bishops they must protect their flocks at all cost from sexually abusive priests, telling them they must investigate sex abuse crimes and prevent pedophiles from entering the priesthood.

Archbishop Charles Scicluna repeatedly cited Pope Benedict XVI in giving a point-by-point tutorial on preventing abuse at a summit of church leaders Thursday. Pope Francis called them to the Vatican to respond to the global sex abuse and cover-up crisis that has undermined credibility in the church.

Scicluna told the bishops that the people of God "should come to know us as friends of their safety and that of their children." He vowed: "We will protect them at all costs. We will lay down our lives for the flocks entrusted to us."