At the synod of Homberg in 1526 he debated with François Lambert, ex-Franciscan, who had become adviser to Philip of Hesse.
[1] At the instance of the bishops of Denmark, he was called to Copenhagen to champion the Catholic cause against Danish Lutheranism.
In Copenhagen he wrote in 1530, the Confutatio Lutheranismi Danici, first edited by L. Schmitt, S.J., and published at Quaracchi (1902), which earned for him the sobriquet of Stagefyr (fire-brand).
Ferber's principal work is entitled: Locorum communium adversus hujus temporis hæreses Enchiridion, published at Cologne in 1528, with additions in 1529.
(Cologne, 1526, and Paris, 1534); and Enarrationes latinæ Evangeliorum quadragesimalium, preached in German and published in Latin (Antwerp, 1533).