A.T. Robertson Commentary Luke 6:26

"Woe [unto you], when all men shall speak well of you! for in the same manner did their fathers to the false prophets." — Luke 6:26 (ASV)

In the same manner did their fathers (τα αυτα εποιουν ο πατερες αυτων). Literally, their fathers did the same things to the false prophets. That is they spoke well (καλως), finely of false prophets. Praise is sweet to the preacher but all sorts of preachers get it.

Of you (υμας). Accusative case after words of speaking according to regular Greek idiom, to speak one fair, to speak well of one.