His planned nuptials to African-American partner Phineas Newborn III in New York had aroused a lot of curiosity amongst the youths, they said, and if left unchecked, would lead to a "morally-bankrupt" society.
The 41-year-old pastor and his 47-year-old partner, a Broadway musical producer, planned to have a Chinese wedding banquet and a traditional tea ceremony in Kuala Lumpur after their marriage in New York at the end of the month.
Grace Assembly Klang Pastor Kam Sian Yee said Ou Yang’s "unnatural sexual behaviour" had flouted many warnings against homosexuality in the Bible.
"His behaviour is not only abnormal, it is a sin in Christianity," Kam said, adding that he had received several complaints from church members.
"We love Ou Yang and hope he will repent," he added.
Puchong Joy Charismatic Centre Pastor Tang Chee Sing urged Ou Yang to "return to the right path".
"Homosexual parents would bring up their children to think that their behaviour is normal.
"This trend cannot go on," he said, stressing that same-sex marriages were a sin despite this being legalised in several American states recently.
"We do not recognise him as a pastor," he said at a press conference hosted by Selangor MCA Public Complaints Bureau chief Datuk Theng Book yesterday.
Theng said he had received complaints from several Christians who worried that society would think that the church condoned gay marriages and homosexuality.