5:20,21 By Christ and his righteousness, we have more and greater privileges than we lost by the offence of Adam. The moral law showed that many thoughts, tempers, words, and actions, were sinful, thus transgressions were multiplied. Not making sin to abound the more, but discovering the sinfulness of it, even as the letting in a clearer light into a room, discovers the dust and filth which were there before, but were not seen. The sin of Adam, and the effect of corruption in us, are the abounding of that offence which appeared on the entrance of the law. And the terrors of the law make gospel comforts the more sweet. Thus God the Holy Spirit has, by the blessed apostle, delivered to us a most important truth, full of consolation, suited to our need as sinners. Whatever one may have above another, every man is a sinner against God, stands condemned by the law, and needs pardon. A righteousness that is to justify cannot be made up of a mixture of sin and holiness. There can be no title to an eternal reward without a pure and spotless righteousness: let us look for it, even to the righteousness of Christ.
20, 21. Moreover the law—"The law, however." The Jew might say, If the whole purposes of God towards men center in Adam and Christ, where does "the law" come in, and what was the use of it? Answer: It
entered—But the word expresses an important idea besides "entering." It signifies, "entered incidentally," or "parenthetically." (In Ga 2:4 the same word is rendered, "came in privily.") The meaning is, that the promulgation of the law at Sinai was no primary or essential feature of the divine plan, but it was "added" (Ga 3:19) for a subordinate purpose—the more fully to reveal the evil occasioned by Adam, and the need and glory of the remedy by Christ.
that the offence might abound—or, "be multiplied." But what offense? Throughout all this section "the offense" (four times repeated besides here) has one definite meaning, namely, "the one first offense of Adam"; and this, in our judgment, is its meaning here also: "All our multitudinous breaches of the law are nothing but that one first offense, lodged mysteriously in the bosom of every child of Adam as an offending principal, and multiplying itself into myriads of particular offenses in the life of each." What was one act of disobedience in the head has been converted into a vital and virulent principle of disobedience in all the members of the human family, whose every act of wilful rebellion proclaims itself the child of the original transgression.
But where sin abounded—or, "was multiplied."
grace did much more abound—rather, "did exceedingly abound," or "superabound." The comparison here is between the multiplication of one offense into countless transgressions, and such an overflow of grace as more than meets that appalling case.