Daniel Zwicker (22 January 1612 – 10 November 1678) was a German physician from Danzig, and a Socinian theologian and controversialist of the Polish Brethren.
[1] He met with considerable opposition, beginning with his brother Friedrich who had succeeded his father as minister.
Meeting some Hutterite missionaries from Slovakia, around 1650, he spent time at Bruderhofs in the community of Andreas Ehrenpreis; but returned to Danzig.
Bull's biographer Robert Nelson considered him an influential Unitarian, writing: He was the first and most considerable of those Unitarian writers, which have fallen under the animadversion of Dr. Bull; for he was before Sandius, and both Sandius and Mr. Gilbert Clerke have but copied in a manner after this learned Dantzicker, as also the rest have done, that have engaged on that side of the controversy.
Following David Blondel's Joanna Papissa (1657) which disproved the historical reality of Pope Joan Zwicker criticized the Joanna Papissa restituta of Samuel Desmarets (Maresius) anonymously, in a work published with those of Étienne de Courcelles.