People still do not appreciate enough that their actions can have unintended consequences for others, especially on social media, said Senior Minister of State for Law and Education Indranee Rajah in a Facebook post on Saturday.

The Tanjong Pagar GRC MP was defending a resident in her ward whose attire Miss Singapore Universe 2013 finalist Jesslyn Tan had mocked in a recent Facebook post.

Mr Koh Hee Huat, 55, was asleep in the MRT and wearing a T-shirt with a hole in it.

Ms Tan, 25, posted a photograph of him on Wednesday with the caption: "Holey moley. Sibei trendy worzxxz."

Sibei is a Hokkien word meaning "very".

Ms Indranee said many people had criticised the post, and Ms Tan had since removed it and apologised for being insensitive, "albeit online and not to Mr Koh directly".

But the MP said she wanted to address the issue from the man's perspective, "so people can understand the impact the episode has had on him".

Her post attracted more than 20,000 "likes", and was shared nearly 4,000 times.

Ms Indranee described the helper at Ye Shanghai Teochew Muay stall at Bukit Merah View as a hardworking man and a familiar face to her and cabbies on the night shift.

He is on his feet from evening until 3am, taking orders and dishing out the food into small plates, she said.

"He makes an honest living to support his mother and his family. His wife works at the same stall. He has a daughter waiting to enter polytechnic," Ms Indranee added.

She said Mr Koh was bewildered why he was singled out.

"His T-shirts have holes because he wears them for work. The stall has metal fixtures, which snag on the T-shirts, causing them to tear. It's just part and parcel of his work environment, in the same way that people who wear overalls may get grease stains, or outdoor workers get dust on their uniforms," she wrote.

Mr Koh also felt a deep loss of face and hurt, as many customers asked him about the comment, and he initially thought of quitting his job because of it, she added.

But his boss encouraged him to keep working, as did she and her grassroots leader.

Ms Indranee urged visitors to the area to encourage him.

"If anyone merits a boost, it is this quiet, hardworking, unassuming man. He may not be sibei trendy but he is definitely 'sibei ho.'" (Hokkien for very good)

Noting the adage "the pen is mightier than the sword" still holds true in the Internet age, she said: "A sword cuts deep but words can cut deeper. We need to have a care in what we say about others."