[1] After two years in Batavia undergoing training and waiting to be assigned a missionary post (where he married his first wife Maria Poots[1]), Gravius went to Formosa in 1647 and was stationed in the village of Soulang.

[3][4] Gravius translated Christian works into the Siraya language, including a formulary, portions of the Bible and various other tracts, which he accompanied with examples to render the meaning clear to the native Formosans.

[7] In 1651 Gravius wrote to Governor Nicolas Verburg complaining about his judicial superior, super-factor Dirck Snoucq, and alleging him to be "a person of shameful and odious character.

"[8] Unfortunately for Gravius, Verburg took the side of Snoucq, declaring that "this cable of infamous slander had been formed of many strands of abuses and misdeeds of so scandalous and unchristian a nature that they cannot even here be mentioned in detail.

[12] Gravius went to Batavia in 1651 to appeal to Governor-General of the Dutch East Indies Carel Reyniersz and his follower Joan Maetsuycker against the verdict handed down by Verburg.