Abusive language by netizens on the wearing of the Muslim headscarf in the public service was criticised by Mufti Mohamed Fatris Bakaram on Monday, as he came out in defence of his predecessor.
Singapore's highest Islamic authority said in a Facebook post that he had pondered for three days whether to weigh in on the issue.
He eventually did, out of concern over the "phenomenon of abusive and disrespectful language from some social media users".
"I am worried that it will be a culture that becomes entrenched in the community if it is not reproached and dealt with," he added.
The tudung issue was raised at a forum on race last month.
A polytechnic lecturer asked why nurses were barred from wearing tudungs, sparking a discussion on whether front-line officers in Singapore should be allowed to.
An online anonymous petition championing the cause was then posted on Oct 12.
It aimed to garner 20,000 signatures, and received only 12,405 before being taken down last week.
Former mufti Shaikh Syed Isa Semait then became embroiled in the issue, after being quoted in a Berita Harian article published last Thursday.
He said the petition could breed misunderstanding, and that one question to ask was whether all Muslim women working at the front line as nurses want to wear a tudung.