The letter was "a general introduction on (in)tolerance, mainly on the subject of predestination and the sacrament... an extensive, detailed and generally unfavourable review of Walaeus' "Ampt", stuffed with references to ancient and modern authorities." When Grotius wrote asking for some notes "he received a treasure-house of ecclesiastical history. ...offering ammunition to Grotius, who gratefully accepted it". Around this time (April 1616) Grotius went to Amsterdam as part of his official duties, trying to persuade the civil authorities there to join Holland's majority view about church politics.