Romans 14:23

23The [one]ὁhoweverδὲdoubtingδιακρινόμενοςifἐὰνhe eatsφάγῃhas been condemnedκατακέκριται,because [it is]ὅτιnotοὐκofἐκfaithπίστεως·everythingπᾶνnowδὲthat [is]ὃnotοὐκofἐκfaithπίστεωςsinἁμαρτίαisἐστίν.

But the one doubting has been condemned if he eats, because [it is] not of faith; and everything that [is] not of faith is sin.