"But God be thanked, that you were the servants of sin, but you have obeyed from the heart that form of doctrine which was delivered you." Romans 6:17
What reason have we to bless God that he so instructed his Apostle to set forth how a sinner is justified! For how could we have attained to the knowledge of this mystery without divine revelation? How could we know in what way God could be just, and yet the justifier of the ungodly? How could we see all the perfections of God harmonizing in the Person and work of Jesus? his law maintained in all its rigid purity and strictest justice, and yet mercy, grace, and love to have full play in a sinner's salvation? But the Spirit of God led Paul deeply into this blessed subject; and especially in the Epistle to the Romans does he trace out this grand foundation truth with such clearness, weight, and power, that the Church of God can never be sufficiently thankful for this portion of divine revelation. His grand object is to show how God justifies the ungodly by the blood and obedience of his dear Son; so that "as by one man's disobedience many were made sinners, so by the obedience of one shall many be made righteous." He declares that "the righteousness of God is unto and upon all those who believe;" and that "through the redemption that is in Christ Jesus, whom God has set forth to be a atoning sacrifice through faith in his blood," he pardons the sinner, justifies the ungodly, and views him as righteous in the Son of his love.
In opening up this subject, the Apostle (Romans 5) traces up this justification to the union of the Church with her covenant Head; shows us her standing in Christ as well as in Adam; and that all the miseries which she derives from her standing in the latter are overbalanced by the mercies that flow from her standing in the former; winding up with that heart-reviving truth, that "where sin abounded, grace did much more abound; that as sin has reigned unto death, even so might grace reign through righteousness unto eternal life."
This then is a "form of doctrine," or mold of teaching, into which the soul is delivered when it is brought into a heart-felt reception of, and a feeling acquaintance with it; and by being led more or less into the experimental enjoyment of it, is favored with a solemn acquiescence in, and a filial submission to it, as all its salvation and all its desire. And as the mold impresses its image upon the moist plaster or melted metal poured into it, so the heart, softened and melted by the blessed Spirit's teaching, receives the impress of this glorious truth with filial confidence, feels its sweetness and power, and is filled with a holy admiration of it as the only way in which God can justify an ungodly wretch, not only without sacrificing any one attribute of his holy character, but rather magnifying thereby the purity of his nature, and the demands of his unbending justice.