“The warfare of Christians relates to the following points:
(1) It is a warfare with the corrupt desires and sensual propensities of the heart; with eternal corruption and depravity, with the remaining unsubdued propensities of a fallen nature.
(2) with the powers of darkness; the mighty spirits of evil that seek to destroy us; see Eph_6:11-17.
(3) with sin in all forms; with idolatry, sensuality, corruption, intemperance, profaneness, wherever they may exist. The Christian is opposed to all these, and it is the aim and purpose of his life as far as he may be able to resist and subdue them. He is a soldier enlisted under the banner of the Redeemer to oppose and resist all forms of evil. But his warfare is not conducted on worldly principles….the people of this world seek for victory by arms and violence; The Christian looks for his conquests only by the force and the power of truth, and by the agency of the Spirit of God.” Barnes Notes on the NT