He was born in Häsleby parish in Jönköping County, to the pastor Nicolaus Petri and his wife, Botilda Olofsdotter, but adopted the surname Verelius in his youth [REF].
Verelius was named to a professorship of Rhetoric at Dorpat in 1652 but never took it up; instead, in 1653 he became steward of the academy at Uppsala, a position which he held until 1657, when he took a teaching position in history.