Scores of supporters of Zuma, most of whom are students from the Durban University of Technology, are there singing songs in support of the former president.
Some African National Congress (ANC) members say they are there to show their support to Zuma because they believe he is being targeted for political reasons.
The supporters have prayed for the former president to be protected by angels on Friday.
Churches, traditional leaders, business forums and Black First Land First are expected to spend most of the night praying for the former president.
Many of them are singing in groups; one song essentially says Zuma will not be prosecuted and that a cow would give birth to a human being if that were to happen.
They believe the former president has been left in the cold by his own party.
Carl Niehaus, who is one of the organisers, says the gathering is important.
“It’s part of what various non-governmental and non-profit organisations and churches thought it’s necessary and, of course, it’s part of the mobilisation process for tomorrow.”
There are stalls selling ANC regalia. Ironically, the ANC has called on its members not to wear its colours as they show support to the former president.
It seems that appeal has been ignored as some supporters there are clad in T-shirts bearing the ANC colours and Zuma’s face.
Around 200 buses are expected to ferry the supporters to court on Friday.
A march and a short prayer are also expected before court begins.