Cheng worked for 10 years as a senior staff worker with the Australian Fellowship of Evangelical Students at the University of Melbourne and then ministered at a number of churches in Sydney.
Since the mid-1990s, Cheng has also written numerous articles for The Briefing, a popular evangelical journal distributed in Australia, England and the United States.
He is a critic of the ordination of women to the priesthood[8] and homosexuality and has written on the priority of Christian ministry over secular work.
His posts defended the actions of a church which was the subject of a defamation lawsuit, involving the sacking of a female lay worker.
[11] More recently, Cheng has been a guest opinion writer for Sydney's Daily Telegraph and Sunday Telegraph newspapers, writing opinion pieces on religious and ethical issues, including Lent,[12] euthanasia,[13] and racism,[14] In late 2006 he was also enlisted by Daily Telegraph columnist Piers Akerman to be a guest writer for a Muslim-Christian debate run by the paper on multiculturalism; others participating included Lebanese Muslim representative Keysar Trad.