He refuted them in his book 't Mom-Aensicht Der Atheistery Afgerukt, "The mask of atheism torn off", published in 1683.

[1] In 1707 Verwer published his Linguae Belgicae Idea, grammatica, poetica, rhetorica; deprompta ex adversariis Anonymi Batavi: in usum proximi amici ("Grammar, poetry and rhetoric of the Belgian language, from the notes of an anonymous Dutchman, for the use of a close friend"), in which he criticises the Nederduitsche spraekkunst[4] of Arnold Moonen, published in the previous year and based on the work of earlier writers such as Joost van den Vondel.

[5] His work was an important influence on two Dutch linguists, his friend Lambert ten Kate (1674–1731), and Balthazar Huydecoper (1695–1778).

Like Verwer, ten Kate was a Mennonite merchant; his Gemeenschap tussen de Gottische Spraeke en de Nederduytsche, "Relationship between the Gothic language and Dutch", published in 1710,[6] was written at Verwer's request, and consists in part of a letter to "A.V.

His copy of the first edition of the Philosophiae naturalis principia mathematica (1687), extensively annotated in his hand, is preserved in the Universiteitsbibliotheek Utrecht.