 He received his episcopal consecration in St. Peter's Basilica on the following 27 December from Pope John, with Bishops Girolamo Bortignon, OFM Cap and Gioacchino Muccin serving as co-consecrators.Ferretto was named Secretary of the College of Cardinals on 20 January 1959.He was created Cardinal-Priest of Santa Croce in Gerusalemme by Pope John in the consistory of 16 January 1961.