And Basuki Tjahaja Purnama, who is commonly known as Ahok, is widely tipped to re-enter Indonesian politics – though that is unlikely to happen until after the April 17 presidential election, according to his long-time friend and human rights campaigner Andreas Harsono.

Ahok, who is an ethnically Chinese Christian, took over as governor of Jakarta when Joko Widodo was elected President in 2014.

In September 2016, Ahok was accused of blasphemy after he suggested a verse of the Koran did not state that Muslims could not be led by a non-Muslim.

The comments triggered sprawling, violent street protests by hardline Islamists, a high-profile trial,  Ahok's shock conviction in May 2017, and struck a blow against pluralism and tolerance in Indonesia that is still being felt more than two years later.

Harsono, who is a researcher for Human Rights Watch Indonesia, suggested Ahok would not quit politics but that "we are in a wait-and-see moment" and that an immediate return was unlikely.

"He is a political animal, not in a negative sense; he is always thinking of how to solve public problems and is a natural politician," he said.

Harsono pointed to a recent, lengthy post by Ahok on Instagram in which he referenced a book containing speeches by Indonesia's founding president, Sukarno.

The title of the book is Unfinished Business – and, according to Harsono, "that was the point that Ahok is wanting to stress, too".

Ahok's release comes in the same week that Indonesian politics has been roiled by a proposal to release the convicted terrorist and spiritual leader of the 2002 Bali bombers, Abu Bakar Bashir.

The potential release of Bashir now looks to have been dropped by a panicked President after strong domestic and international criticism, but both cases point to the growing influence of Islam in political debate in the world's largest Muslim-majority democracy.

Indonesian media has reported that Ahok, 52, is set to marry for a second time on February 15 to a 23-year-old policewoman named Puput Nastiti Devi. There has also been speculation that he could convert to Islam to smooth the way for the marriage to go ahead, as inter-religious marriage is difficult – though not impossible – in the archipelago.

The conviction of Ahok is one of a number of high-profile recent cases involving Indonesia's controversial blasphemy laws.

Last April, Sukmawati – the daughter of former president Sukarno – delivered a grovelling apology after being threatened with legal sanction under blasphemy law for allegedly insulting Muslims in a poem she wrote years previously.

In August, a woman in North Sumatra was jailed for 18 months after claiming the adzan, or call to prayer, from her local mosque was too loud.

Dr Melissa Crouch, an expert in Indonesia's blasphemy laws from the University of NSW, said the blasphemy law had been "weaponised" in recent years.

"It's called 'the Ahok effect', the use of the blasphemy law to target political opponents," she said.

"Ahok's release is a reminder of what could have been. He was once Jokowi's [the nickname for Widodo] running mate and deputy governor. If things had gone well, he could have been vice-president. There is that sense of a missed opportunity to have a minority Chinese Christian [in high office]."

Ahok is currently being held in the Mako Brimob prison, a high-security prison usually used for convicted terrorists.

The former governor has even asked his hundreds of thousands of supporters to no longer call him by his Hakka Chinese name, Ahok, but rather to call him “BTP” – short for his full name, Basuki Tjahaja Purnama – when he is released.

with Karuni Rompies