But seeing that all the desires of the flesh are enmity against God, the first step to the obedience of his law is the renouncement of our own nature. Renovation is afterwards manifested by the fruits produced by it—viz. justice, judgment, and mercy. Since it were not sufficient duly to perform such acts, were not the mind and heart previously endued with sentiments of justice, judgment, and mercy this is done when the Holy Spirit, instilling his holiness into our souls, so inspired them with new thoughts and affections, that they may justly be regarded as new.
In one word, then, by repentance I understand regeneration, the only aim of which is to form in us anew the image of God, which was sullied, and all but effaced by the transgression of Adam. So the Apostle teaches when he says, “We all with open face beholding as in a glass the glory of the Lord, are changed into the same image from glory to glory, as by the Spirit of the Lord.” Again, “Be renewed in the spirit of your minds” and “put ye on the new man, which after God is created in righteousness and true holiness.” Again, “Put ye on the new man, which is renewed in knowledge after the image of him that created him.” Accordingly through the blessing of Christ we are renewed by that regeneration into the righteousness of God from which we had fallen through Adam, the Lord being pleased in this manner to restore the integrity of all whom he appoints to the inheritance of life. This renewal, indeed, is not accomplished in a moment, a day, or a year, but by uninterrupted, sometimes even by slow progress God abolishes the remains of carnal corruption in his elect, cleanses them from pollution, and consecrates them as his temples, restoring all their inclinations to real purity, so that during their whole lives they may practice repentance, and know that death is the only termination to this warfare.
By regeneration the children of God are delivered from the bondage of sin, but not as if they had already obtained full possession of freedom, and no longer felt any annoyance from the flesh. Materials for an unremitting contest remain, that they may be exercised, and not only exercised, but may better understand their weakness. All writers of sound judgment agree in this, that, in the regenerate man, there is still a spring of evil which is perpetually sending forth desires that allure and stimulate him to sin. They also acknowledge that the saints are still so liable to the disease of concupiscence, that, though opposing it, they cannot avoid being ever and anon prompted and incited to lust, avarice, ambition, or other vices…Accordingly, we hold that there is always sin in the saints until they are freed from their mortal frame, because depraved concupiscence resides in their flesh, and is at variance with rectitude. Augustine himself dose not always refrain from using the name of sin, as when he says, “Paul gives the name of sin to that carnal concupiscence from which all sins arise. This in regard to the saints loses its dominion in this world, and is destroyed in heaven.” In these words he admits that believers, in so far as they are liable to carnal concupiscence, are chargeable with sin.
In regenerating his people God indeed accomplishes this much for them; he destroys the dominion of sin, by supplying the agency of the Spirit, which enables them to come off victorious from the contest. Sin, however, though it ceases to reign, ceases not to dwell in them. Accordingly, though we say that the old man is crucified, and the law of sin is abolished in the children of God, the remains of sin survive, not to have dominion, but to humble them under a consciousness of their infirmity. We admit that these remains, just as if they had no existence, are not imputed, but we, at the same time, contend that it is owing to the mercy of God that the saints are not charged with the guilt which would otherwise make them sinners before God.
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