[1] Most of these people were Catholics, but were given their freedom on the condition that they joined the Dutch Reformed Church, and the converts were known as Mardijker or the liberated ones.

[citation needed] The first sermon was delivered by Reverend Theodorus Zas and was attended by Governor-General Willem van Outhoorn.

The building is protected through the Law SK Gubernur DKI Jakarta CB/11/1/12/1972[5] In 1984, the churchyard was reduced for road construction.

[5] Sion Church is characteristically Dutch with its plain facade, ward-like appearance and domed windows.

[7] The ornate bronze tombstone of Governor-General Hendrick Zwaardecroon, who died in 1728, was buried, as was his wish, among "ordinary" people.