Cornelius Sim DD (16 September 1951 – 29 May 2021) was a Bruneian prelate of the Catholic Church who served as Vicar Apostolic of Brunei from 2004 until his death. He had previously served as the apostolic prefect of Brunei from 1997 to 2004.
Sim was the first graduate of Franciscan University of Steubenville priestly discernment program to be ordained to the priesthood. Pope Francis raised him to the rank of a cardinal on 28 November 2020, making him the first cardinal from the country, and from the island of Borneo. Sim has been credited as "Brunei's most famous Catholic" and a "towering figure" in the history of Bruneian Christianity.
Sim was born in Seria, Brunei, on 16 September 1951. He was the eldest of six children of Lawrence Sim and Monica Yeo, and his grandparents were the first Catholics in their village, with the Church's history in Brunei documented most prominently from the 19th century onwards. He was of Chinese and Dusunic descent. He was raised a Catholic and educated in Catholic schools, but practised his faith less as he reached adulthood.
Sim earned an engineering degree from Dundee University in Scotland. After this he stopped practising his faith. He worked in utilities operations of Brunei LNG, a joint-venture between the Bruneian government, Royal Dutch Shell and Mitsubishi, from 1978 to 1985; he spent some of these years working abroad. Returning to Brunei, he rediscovered his Catholic faith and grew close to a charismatic group that downplayed doctrine and emphasised personal relationships with God. He earned a master's degree in theology at the Franciscan University of Steubenville, Ohio, in 1988. He returned to Brunei in 1988 and served as an administrator in St John's Church, Kuala Belait until his ordination as deacon on 28 May 1989.
Sim was ordained to the priesthood on 26 November 1989. He became the country's first local priest. He served the faithful in Brunei alongside two other missionary priests resident in Brunei, until 1991. Following this, Sim served all parishes as the sole priest in Brunei for an indefinite period during which he pledged that there would be "no let up" in services to the faithful. He was appointed vicar general of Brunei in 1995, which was part of the Diocese of Miri in Malaysia at the time. After Brunei was split from Miri to form the Apostolic Prefecture of Brunei, Pope John Paul II named Sim apostolic prefect on 21 November 1997. He was installed there on 23 February the following year.
Sim attended the 1998 Asia Synod of Bishops and was observed as a "young prefect apostolic" at the time. Three years later in 2001, Sim also attended the ad limina visit to Pope John Paul II by prelates from the Bishops' Conference of Malaysia, Singapore and Brunei.
Pope John Paul II elevated the Prefecture of Brunei to the status of a vicariate and appointed Sim the first Apostolic Vicar of Brunei and Titular Bishop of Putia in Numidia on 20 October 2004.
He received his episcopal consecration on 21 January 2005 from Archbishop Salvatore Pennacchio at the Church of Our Lady of the Assumption in Bandar Seri Begawan. The co-consecrators were John Ha Tiong Hock, Archbishop of Kuching and Anthony Lee Kok Hin, Bishop of Miri. He requested that his ordination be held in Brunei rather than Rome, so that the local faithful could take part. On a number of occasions, Sim publicly advocated for peaceful and tolerant relations among Bruneians of all religious affiliations. He was also involved in the activities of schools operating under his authority, publicly attending functions such as Chinese New Year. Sim frequently acted as the representative of the Christian community in Brunei during government engagements locally and abroad, including with foreign diplomatic missions, local ministries and the supreme court. Sim also made visits to overseas missions such as in Timor Leste.
As the first local bishop in Brunei, Sim introduced seven priorities for the local Church: adult faith formation, Bible literacy, youth, family, vocations, evangelisation and social welfare, particularly for migrants.
In June 2005, Sim welcomed the Holy See's foreign minister to Brunei, who during his visit met with Brunei's deputy sultan.
Sim made an ad limina visit on 5 June 2008 to the Apostolic Palace in the Vatican for an audience with Pope Benedict XVI.
As far back as 2012, Sim is reported to have been celebrating red masses in Brunei or in neighbouring dioceses.
On 15 July 2014, Sim backed calls made by Brunei's reigning sultan to the country to pray for peace in Palestine amid rising tensions. Sim urged Catholics to pray for peace, and also pledged the Catholic Church's support towards Brunei government aid initiatives.
Sim celebrated his 10th episcopal anniversary and coincidentally his silver jubilee of ordination to the priesthood on 21 January 2015 with a commemorative Mass at the Church of Our Lady of the Assumption in Bandar Seri Begawan. The Mass was concelebrated with the other resident priests from Brunei, as well as several prelates and guest priests representing neighbouring dioceses from the Philippines, Kota Kinabalu, Sandakan, Keningau and Singapore, as well as the Apostolic Delegation to Brunei Darussalam. In the following days, Sim and the visiting apostolic delegate attended an audience ceremony at one of the Brunei royal houses.
On 8 February 2018, Sim made an ad limina visit to the Vatican for an audience with Pope Francis.
After mid-2018, Sim spoke of the present day need for Christians to counter the spread of 'fake news' in the media.
In May 2018, Sim publicly attended the silver jubilee celebrations at the Kota Kinabalu archdiocese.
Sim frequently attended Confirmation retreats throughout Southeast Asia.