SINGAPORE - Mr David Chong has spent 36 years of his life behind bars, having been in and out of prison more than 10 times, mostly for drug offences.

After he was released from prison in 2014 following a close to eight-year stint for drug trafficking, he found staying clear of drugs difficult but was able to turn his life around through his religion.

Mr Chong, 58, has not been back in prison since.

The part-time food delivery driver is among the Singapore Anti-Narcotics Association's (Sana) 474 volunteers and he shares his experience with drug offenders to help them overcome their addiction.

Speaking to the media on Wednesday (June 22) ahead of a celebration on Saturday for Sana's 50th anniversary this year, Mr Chong recalled his struggles after his last prison stint.

On Chinese New Year in 2015, after being given time off by the halfway house he was residing in, he had gone to Geylang in search of a drug fix.

He could not find any and returned to the halfway house frustrated at himself.

"I thought to myself, how come every time I am given freedom, I go back to drugs," he said.

Mr Chong, a Christian, prayed and woke up early the next morning and read the Bible and listened to worship songs.

Two months after he started the ritual, he was in a public toilet when he found a straw of drugs on the floor, which he flushed down the toilet bowl.

"This gave me (a feeling of) victory... Last time, if I were to see drugs, I would surely yield to the temptation, but now I can resist," he said.

Mr Chong joined Sana as a volunteer in 2018 and speaks to about 50 inmates in prison once a month, sharing his life experience with them.

The former gang member feels that imparting his own experience is an important step in helping offenders transform.

He said: "They will think 'This fellow with tattoos, (many) times in prison... if he can change, I also can change.'"

Mr Percival Shepherdson, 75, has been a Sana volunteer for 25 years.

The retired chef began his stint conducting a food hygiene course for inmates till about six years ago.

About 1,300 inmates had undergone the three-day course, following which they could get certified and work in a kitchen.

He had also organised watercolour courses for psychiatric inmates and about 80 inmates have learnt painting skills from a qualified artist through the course.

His new beneficiaries in recent years are Sana volunteers. He is chairman of the association's volunteer club, which organises activities for volunteers.

Mr Percival, who has more than 50 years of counselling experience, said empathy and compassion are essential traits for volunteers.

"To be a volunteer means you are signing up for the long term. Some people sign up expecting miracles, that they can change the client in a day - there is no such thing. You have to be there for him any time he needs you, it is not easy."