Before Hamzah Fansuri, Malay was a language of trade, chronicle and romance. He made it carry technical mystical argument, and he did it in two registers at once.
The first is the syair, a poem in four-line stanzas with a single end rhyme, which he is generally credited with introducing into Malay and which became one of the standard forms of the literature. His poems are short, direct and full of concrete images taken from the sea and the trades of a port: the wave that is not other than the ocean, the fish that seeks water while swimming in it, the shadow-play figure moved by an unseen hand. Each carries a technical point about the relation of the manifest world to the being that underlies it.
The second is prose treatise, of which three are usually named. Here he writes as a theologian in the line of Ibn Arabi, expounding the unity of being, the seven grades of descent by which the absolute becomes manifest, and the vocabulary of essence, attribute and act. He quotes Arabic and Persian authorities and glosses them in Malay, which required inventing much of the vocabulary as he went.
The combination is what gave the work its reach. A reader who could not follow the treatise could learn the poems by heart, and the poems circulated across the archipelago far beyond the scholarly circles the prose addressed.