A former assistant pastor was sentenced to 16 months jail on Friday for making a 15-year-old girl from his church perform oral sex on him twice.

Both cannot be identified because of a gag order to prevent the identification of the victim but the court heard that in one of those incidents, the offence was committed on church grounds and the other at a park in 2011.

The 46-year-old man, who is married with three children of his own, also faced a third charge of committing an obscene act that was considered during his sentencing.

The accused was in charge of the church's youth group, and had organised programmes and activities for its younger members. He and the victim were apparently in a relationship after having expressed their love for each other.

The pair had started chatting via text messaging. Their conversations became progressively more intimate and sexual in nature, said Deputy Public Prosecutor Ng Yiwen, adding that the accused would talk to the victim about sex and intimated that he wanted to have sex with her.

Sometime between end-September and early October of 2011, he made her perform oral sex on him at a secluded part of a park. The second time she did it was in October when she went to help him with some chores in church.

It was only after she left for a school trip in Beijing later that month that she realised that what the accused had done was wrong. She then sent a text message to her mother who then flew to Beijing with her husband to escort her back. A police report was later filed on Nov 22 that year.