On 26 June 1526, Johann held a Lutheran service in the City Church of Waldeck and thereby officially introduced Lutheranism in the County of Waldeck, four months before Landgrave Philip I, Landgrave of Hesse introduced the Reformation in neighbouring Hesse at the Synod of Homberg.

following the advice of the reformer Adam Krafft, founded the Lutheran State Church of Waldeck at the monastery in Volkhardinghausen.

Johann Hefentreger was appointed visitor and later implemented the order of the two counts to dissolve the monasteries, following the Hessian example.

Monasteries were dissolved at Berich, Flechtdorf, Netze, Ober-Werbe, Schaaken and Volkhardinghausen, but with the proviso that they would remain open until the death of the last spiritual resident.

He was buried on 4 December 1574 in the family burial vault in the Nicholas chapel of the church of Marienthal monastery in Netze (now part of the city of Waldeck.