Let it be so, that you will only engage with those who bear the image of the living God, who have come into this world by birth, and who have repented and called upon the name of the Lord Jesus Christ for salvation. This is a good confession, for what fellowship has light with darkness, or what part has he that believes with an infidel? Yet take heed that this very zeal does not become a stumbling stone to you, as the Lord Himself is to the unbelieving. Is He not laid in Zion as a stone of stumbling and a rock of offense? Be sure that you are not among those who stumble at the Word, being disobedient, while professing to stand for the Truth. For many there are who say, "Lord, Lord," and yet do not the things which He commands. The repentance that brings salvation is not a loud declaration of our own standards, but a weeping at the foot of the Cross, a turning from sin because of the love of God who died for us. That is saving repentance, which avoids present sin not out of pride, but out of love for the bleeding Savior. Beware of a repentance that brings no glory to God, that makes a fair show in the flesh but has no trace of submission, no touch of faith, no breath of love.
You speak of being created in the image of God, and well you should. Man was a noble creature when he was made in that image, but sin blotted out all his dignity. That image is restored only in Christ, who is the image of the invisible God, the firstborn of every creature. The children of God, born again by the Spirit, are led to bear a high degree of likeness to their heavenly Father. They are led to repentance, yes, but also into love, and into the warmth of that divine fellowship with God which was lost in the Garden. Have you known this fellowship? The Spirit bears witness with our spirits that we are born of God. If you have been brought nigh by the blood of Christ, then your deepest feelings, like the inwards and the fat upon the altar, are to be with God alone. Love is the true test of light, love to God, love to Christ, love to the Truth, love to God's people. Do you love the whole family of the redeemed? He that does not love the brother whom he has seen, how can he love God whom he has not seen?
I fear lest your words, though firm, might betray a thought that God is the God of the hills and not the God of the valleys. Can He only keep you in the high places of visible triumph, and not in the lowly valley of this present confusion? The Syrians blasphemed thus, and God delivered Israel. But our own proud thoughts may lead us into similar profanities. Do we dream that He cannot preserve His Truth unless we build a wall of separation by our own rules? The church of the living God is the pillar and ground of the Truth, and that church is composed of all who hold the Truth as it is in Jesus, not those who merely adopt a cant phraseology of exclusivity. Believers are not always those whom we would suppose to be believers. We may go in and out of the house of God and yet be strangers in the presence of the Most High. The Word of God is our heritage, our joy, and our delight. He will not let a man die who delights in His Law. If you love the Law of God, the Word of God, the will of God, the way of God, He will not let you die.
But see to it that your joy is in the testimonies of God and not in the strength of your own resolve. There is no joy like that of believing the testimonies of God, accepting the Covenant of Grace, and living upon the Christ of God. Your business is to tell the Gospel to every sort of sinner, to every class of mind and to every rank of persons. The Gospel of the Grace of God is the best vindication of His Law. Let your engagement with men, therefore, be not merely a test of their humanity, but a sweet invitation to the Fountain opened for sin and uncleanness. For if the very sin of man is made to turn to the glory of God, then let us declare that mercy to the chief of sinners. Obedience to the will of God is the pathway to perpetual honor and everlasting joy.