Now the Islamic cleric sees it as her duty to don the head covering while in public.
But the self-proclaimed feminist questions why other Indonesian women wear it, when it's not compulsory to do so.
"Today I can see the hijab is a commodity, it is a tool to politicise religion," the 58-year-old told the ABC.
"In Indonesia a lot of people wear the hijab, even those who don't really understand the religion. Sometimes I ask them, why are you wearing the hijab for?"
There are no government statistics on how many Indonesian women wear a Muslim head covering.
But it's widely accepted that since the fall of Suharto in 1998, more women are covering up, with the emergence of democracy allowing Islamic groups greater influence.
Alissa Wahid, a daughter of the late moderate President Abdurrahman Wahid or Gus Dur, began wearing a lose fitting batik headscarf in recent years to set an example to Indonesian women about how traditionally the head cover should be worn.
"I don't feel it is compulsory for women to wear it in a certain way and because I am Indonesian this is the way that Indonesian women wear their headscarf," she said.
"For me it is as simple as that, it is more like a mix of religion and the Indonesian culture."
Sharia-style clothing 'widely accepted': designer
Research conducted by the Jakarta based Alvara Research Centre in 2015 showed 79.4 per cent of respondents preferred to wear a regular hijab, while 13.5 per cent preferenced the more conservative longer sharia-style hijab, which covers the breasts and buttocks.
Fashion designer Cynthia Mahendra began wearing the sharia-style covering at her husband's insistence and started designing her own after finding them difficult and expensive to purchase in Jakarta.
"Based on the Islamic rules, the guidance for clothing is it should not shape a woman's body, it should not curve at the bottom and the chest. The hijab I wear is lose from head to toe," she said.
She now sells up to 3,000 sharia-style hijabs a month.
"I think now days the sharia clothing has been accepted widely, whereas before women were reluctant to wear it," Ms Mahendra said.
"So many women understand the Islamic rules and moved themselves from the casual hijab to the sharia hijab."
Wearing the niqab shows 'faith has been tested'
In 2015, the Alvara Research study showed less than 2 per cent of Indonesian women surveyed preferred wearing the niqab or burqa, both of which cover the face.
Ms Wahid said she did not mind women wearing the burqa if they were not forced to do so, but she was not critical of the ban against it in other countries.
"I can understand the public policies that are implemented in France or in some other areas in Europe," she said.
"It poses more threats concerning security and also the potential for social conflict."
Professor Mulia also had no problem with the burqa being banned.
"I agree with that, as a lecturer at an Islamic University I said to my dean that I refuse to let my students cover their faces because I would like to have the security that they're really my students."
"In my class they need to uncover their faces to enter and once they get to the class then they can wear whatever they like."
But as her sharia hijab business booms, Ms Mahendra spoke of her desire for all Muslim women to wear the niqab or to fully cover their face, something she herself is striving for.
"All Muslim women want to wear the niqab because after they wear it then they become perfect Muslim women," she said.
"It means their faith has been tested, they don't feel the need to show their faces, they no longer have worldly desires because they aim for afterlife."