In October 1980,
Pope John Paul II named Onaiyekan to a five-year term on the
International Theological Commission. In November, he joined the International Catholic/Methodist Dialogue Commission. He received his episcopal consecration on 6 January 1983 by Pope John Paul II. He was named Bishop of Ilorin on 20 October 1984. On 7 July 1990 he was appointed
coadjutor bishop of
Abuja. When that diocese became an
Archdiocese on 26 March 1994, Onaiyekan became its first archbishop. In 2009 the archbishop entered into a widely televisied debate with church-critics
Christopher Hitchens and
Stephen Fry on whether the catholic Church is a force for the good. On 18 September 2012,
Pope Benedict XVI named Onaiyekan one of the Synod Fathers for the October 2012 Ordinary General Assembly of the
Synod of Bishops on the New Evangelization. He was created a
cardinal by Pope Benedict XVI in a
consistory on 24 November 2012. As
Cardinal-Priest he was assigned to the
titular church of
San Saturnino. On 31 January 2013,
Pope Benedict XVI appointed Onaiyekan a member of the
Congregation for the Doctrine of the Faith (CDF) and a member of the Presidential Committee of the
Pontifical Council for the Family. He can hold these positions until his 80th birthday. He was one of the
cardinal electors who participated in the
2013 papal conclave that elected
Pope Francis. Pope Francis appointed Onaiyekan the
Apostolic Administrator of the
diocese of Ahiara in Imo State in eastern Nigeria on 3 July 2013. Pope Francis appointed him to a five-year renewable term as a member of the
Congregation for Divine Worship and the Discipline of the Sacraments in October 2016. He won the election for the position of
Christian Association of Nigeria (CAN) President on 19 June 2007 with 72 votes over Anglican Primate
Peter Akinola who had 33 votes. In 2010 he was succeeded by
Ayo Oritsejafor. Pope Francis accepted his resignation as Archbishop of Abuja on 9 November 2019. == Honours ==