Petrus Serrarius

Petrus Serrarius (1600–1669; born in London) was a Dutch millenarian theologian. He was a merchant by profession. He has been called the dean of the independent, dissident religious thinkers of Amsterdam. He was a close associate and protector of Baruch Spinoza. Popkin describes him as Spinoza's contact with the outside world.

He was a Collegiant, and is said by Richard Popkin to be of Scottish extraction; his name at birth was Serrurier, his family was Walloon. He studied at Christ Church, Oxford from 1617 to 1619.

He associated also with Adam Boreel, John Dury, and Menasseh ben Israel. He was a correspondent of Samuel Hartlib. His involvement with Judaism led him to gematria, and a belief in Sabbatai Zevi, which may not have extended to his messianic claims.

He published works on the millennium. As well as being a philosemite, interested greatly in the issue of the Lost Tribes, he was on good terms with the Amsterdam Quakers, and had been in contact with William Ames. He corresponded with the Baptist Henry Jessey.

Initially an orthodox Calvinist, he had left his church before coming to Amsterdam around 1630. He attacked the views of Moses Amyraut, who had in Du règne de mille ans ou de la Prospérité de l'Église (1654) taken up a position against the millenarians of the time. Serrarius replied with Assertion du règne de mille ans (1657). He in turn was attacked by Samuel Maresius, a pupil of Franciscus Gomarus. Maresius attempted to undermine the appeal to the work of Joseph Mede made by Serrarius.

He was also one of the critics of Lodewijk Meyer.