The law concerning the papal elections has been changed in the meantime When Stephen was elected it was neccessary to receive episcopal consecration to assume the papal office After the Decree In Nomine Domini of Pope Nicholas II  the elect could have exercised papal office immadiately after his election no matter whether already bishop or not Besides it is neccessary to distinguish the rites of episcopal consecration and of coronation Celestine IV received episcopal consecration in  three years before his election to the papacy because in this year he became bishop of Sabina He died before coronation but not before episcopal consecration Stephen was not a bishop when elected pope