I. "I say, Walk by the Spirit, and you will verily not fulfil the lust of the flesh." On what ground does this bold assurance rest? Because, the Apostle replies, _the Spirit and the flesh are opposites_ (ver. 17). Each is bent on destroying the ascendency of the other. Their cravings and tendencies stand opposed at every point. Where the former rules, the latter must succumb. "For the flesh lusteth against the Spirit, and the Spirit against the flesh." The verb _lust_ in Greek, as in English, bears commonly an evil sense; but not necessarily so, nor by derivation. It is a sad proof of human corruption that in all languages words denoting strong desire tend to an impure significance. Paul extends to "the desire of the Spirit" the term which has just been used of "the lust of the flesh," in this way sharpening the antithesis.[140] Words appropriated to the vocabulary of the flesh and degraded by its use, may be turned sometimes to good account and employed in the service of the Holy Spirit, whose influence redeems our speech and purges the uncleanness of our lips. [140] Comp. Jas. iv. 5: "The Spirit which He made to dwell in us, yearneth even unto jealous envy" (_R. V. margin_); also the double use of ζηλόω in ch. iv. 17, 18 (Chapter XVIII, pp. 279, 280.). The opposition here affirmed exists on the widest scale. All history is a battlefield for the struggle between God's Spirit and man's rebellious flesh. In the soul of a half-sanctified Christian, and in Churches like those of Corinth and Galatia whose members are "yet carnal and walk as men," the conflict is patent. The Spirit of Christ has established His rule in the heart; but His supremacy is challenged by the insurrection of the carnal powers. The contest thus revived in the soul of the Christian is internecine; it is that of the kingdoms of light and darkness, of the opposite poles of good and evil. It is an incident in the war of human sin against the Holy Spirit of God, which extends over all time and all human life. Every lust, every act or thought of evil is directed, knowingly or unknowingly, against the authority of the Holy Spirit, against the presence and the rights of God immanent in the creature. Nor is there any restraint upon evil, any influence counteracting it in man or nation or race, which does not proceed from the Spirit of the Lord. The spirit of man has never been without a Divine Paraclete. "God hath not left Himself without witness" to any; and "it is the Spirit that beareth witness, because the Spirit is truth." The Spirit of truth, the Holy Spirit, is the Spirit of all truth and holiness. In the "truth as it is in Jesus" He possesses His highest instrument. But from the beginning it was His office to be God's Advocate, to uphold law, to convict the conscience, to inspire the hope of mercy, to impart moral strength and freedom. We "believe in the Holy Ghost, the Lord and Giver of life."