He came into relations with John a Lasco, and with Menno Simons.
Menno was not satisfied with the inconsistent answers which he got from Luther, Bucer and Bullinger; he resolved to rely on Scripture alone, and from this time describes his preaching as evangelical, not sacramental.
A brother of Menno joined the insurgent followers of John Matthyszoon, and was killed at Bolsward (April 1535).
Blaming the leaders by whom these poor people had been misled, Menno blamed himself for not having shown them a straight course.
The subsequent career of Menno was that of an active missioner; his changes of place, often compulsory, are difficult to trace.