Mark 1:34 Commentary - Whedon's Commentary on the Old and New Testaments

34. Suffered not the devils to speak See notes on Mar 1:25. Some good critics render this clause, “suffered not the devils to say that they knew him.” His peremptory and stern dealing with these malignant beings was to show his abhorrence, of their malignant nature. Moreover, he thereby taught us at this day not to found our faith on pretended spiritualistic manifestations from unknown supernatural sources or sorceries. If we trust in that class of deceptions we are liable to be betrayed by them into damnable falsehood and delusion.