who sponsored a council of bishops which reaffirmed the nicene creed
Nicene Creed The third Ecumenical Council (Council of Ephesus of 431) reaffirmed the original 325 version[31] of the Nicene Creed and declared that "it is unlawful for any man to bring forward, or to write, or to compose a different (ἑτέραν) faith as a rival to that established by the holy Fathers assembled with the Holy Ghost in Nicaea" (i.e., the 325 creed). The word ἑτέραν is more accurately translated as used by the Council to mean "different", "contradictory", rather than "another".[32][32] This statement has been interpreted as a prohibition against changing this creed or composing others, but not all accept this interpretation.[32] This question is connected with the controversy whether a creed proclaimed by an Ecumenical Council is definitive in excluding not only excisions from its text but also additions to it.
Second Vatican Council The Second Vatican Council, fully the Second Ecumenical Council of the Vatican[2] (Latin: Concilium Oecumenicum Vaticanum Secundum) and informally known as Vatican II, addressed relations between the Catholic Church and the modern world.[3] It was the twenty-first and most recent ecumenical council of the Catholic Church and the second to be held at St. Peter's Basilica in the Vatican. The council, through the Holy See, formally opened under the pontificate of Pope John XXIII on 11 October 1962 and closed under Pope Paul VI on the Feast of the Immaculate Conception on 8 December 1965.