A.W. Pink: Transgressing the Law and paying the penalty does not remove the positive obligation for perfect righteousness

The one who was justified upon his believing sustained a twofold relation unto God: first, he was a responsible creature, born under the law; second, he was a criminal, having transgressed that law—though his criminality has not canceled his obligation to obey the law any more than a man who recklessly squanders his money is no longer due to pay his debts. Consequently, justification consists of two parts, namely, an acquittal from guilt, or the condemnation of the law (deliverance from Hell), and the receiving him into God’s favour, on the sentence of the law’s approval (a legal title to Heaven). ... Against this it has been objected, "The law requires no man to obey and die too." To which we reply in the language of J. Hervey (1750), "But did it not require a transgressor to obey and die? If not, then transgression robs the law of its right, and vacates all obligation to obedience. … It is not sufficient that the believer stand before God with no sins upon him—that is merely negative. The holiness of God requires a positive righteousness to our account—that His Law be perfectly kept. But we are unable to keep it, therefore our Sponsor fulfilled it for us.” –A.W. Pink, “Justification” (ch. 5)