I. The Definition and Forensic Nature of Justification
"Justification is a judicial act of God, in which He declares, on the basis of the righteousness of Jesus Christ, that all the claims of the law are satisfied with respect to the sinner." [Louis Berkhof - Systematic Theology]
"A man is said to be justified in the sight of God when in the judgment of God he is deemed righteous, and is accepted on account of his righteousness; for as iniquity is abominable to God, so neither can the sinner find grace in his sight, so far as he is and so long as he is regarded as a sinner." [John Calvin - Institutes]
"For Scripture places the forensic, juridical meaning of justification beyond all doubt... It means to acquit someone after judicial investigation of the guilt, to declare righteous..." [Herman Bavinck - Reformed Dogmatics]
"Righteousness is conformity with the law; or, it is the fulfilling of the law, or that by which we are justified before God. Justification, on the other hand, is the application of this righteousness to any one. They differ, therefore, as shape and the application of it to an object, or as whiteness and whitening, or making white." [Zacharias Ursinus - Commentary on the Heidelberg]
"To justify, therefore, is nothing else than to acquit from the charge of guilt, as if innocence were proved. Hence, when God justifies us through the intercession of Christ, he does not acquit us on a proof of our own innocence, but by an imputation of righteousness, so that though not righteous in ourselves, we are deemed righteous in Christ." [John Calvin - Institutes]
"Justification is an act of God's free grace, wherein he pardoneth all our sins, and accepteth us as righteous in his sight, only for the righteousness of Christ imputed to us, and received by faith alone."
II. The Two Elements of Justification: Pardon and Acceptance
"Our justification doth consist in two things. 1. In the pardon of our sins. 2. In the acceptation of us as righteous." [Thomas Vincent - The Shorter Catechism]
"Justification and the forgiveness of sins are, therefore, the same: for to justify is that God should not impute sin unto us, but accept of us and declare us righteous; or, which is the same thing, that he declare us righteous on the ground of the righteousness of Christ made over unto us." [Zacharias Ursinus - Commentary on the Heidelberg]
"The righteousness of Christ, which is imputed to us for our justification, is his whole obedience to the law in our stead, and that both his passive obedience in all his sufferings, especially in his death, whereby we have the pardon of all our sins... and his active obedience also, whereby we are accepted as righteous in God's sight..." [Thomas Vincent - The Shorter Catechism]
"Justification, or the remission of sins. The justice of God demands that the sinner should not be punished twice. And as he has punished our sins in Christ, he will not, therefore, punish the same in us." [Zacharias Ursinus - Commentary on the Heidelberg]
"Thus we simply interpret justification, as the acceptance with which God receives us into his favor as if we were righteous; and we say that this justification consists in the forgiveness of sins and the imputation of the righteousness of Christ" [John Calvin - Institutes]
III. The Ground of Justification: The Imputed Righteousness of Christ
"The righteousness with which we are here justified before God, is not our conformity with the law, nor our good works, nor our faith; but it is the satisfaction which Christ rendered to the law in our stead; or the punishment which he endured in our behalf" [Zacharias Ursinus - Commentary on the Heidelberg]
"Hence also it is proved, that it is entirely by the intervention of Christ's righteousness than we obtain justification before God. This is equivalent to saying that man is not just in himself, but that the righteousness of Christ is communicated to him by imputation, while he is strictly deserving of punishment." [John Calvin - Institutes]
"In the Old Testament and in the New, God is declared to be just, in the sense that his nature demands the punishment of sin; that therefore there can be no remission without such punishment, vicarious or personal; that the plan of salvation... involves the substitution of the incarnate Son of God in the place of sinners, who assumed their obligation to satisfy divine justice..." "simply means that his righteousness, having been wrought out by Christ for the benefit of his people, in their name, by Him as their representative, it is laid to their account, so that God can be just in justifying the ungodly." [Charles Hodge - Systematic Theology]
"With remission of sin is joined imputation of righteousness." [Thomas Watson - The Lord's Prayer]
IV. The Exclusion of Works and Human Merit
"For Scripture testifies that from the works of the law no flesh can or will be justified, Jes. 64:6, Rom. 3:19, 20, 8:7, Ef. 2:2 etc." [Herman Bavinck - Reformed Dogmatics]
"The sum is, that man cannot claim a single particle of righteousness to himself, without at the same time detracting from the glory of the divine righteousness." [John Calvin - Institutes]
"It is necessary that that righteousness which will stand in the judgment of God must be absolutely perfect, and conformable to the law in every respect. But our best works in this life are imperfect, and defiled with sin. Therefore our best works cannot be the whole, nor even a part of our righteousness before God." "Augustin has correctly said: 'Good works do not precede them that are to be justified, but follow them that are justified.'" [Zacharias Ursinus - Commentary on the Heidelberg]
"Believers are to make great use of the moral law—but they must trust only to Christ's righteousness for justification; as Noah's dove made use of her wings to fly—but trusted to the ark for safety." [Thomas Watson - The Ten Commandments]
V. The Instrumental Office of Faith
"We are said to be justified by faith only: 1. Because we are justified by the object of faith alone, that is by the merits of Christ only, without which we can have no righteousness whatever: for we are justified for Christ's sake." [Zacharias Ursinus - Commentary on the Heidelberg]
"We are justified only by faith, and neither in whole nor in part by works." [Thomas Vincent - The Shorter Catechism]
"Faith does not justify by its essence or act, because it itself is righteousness, but by its content, because faith is in Christ, our righteousness." [Herman Bavinck - Reformed Dogmatics]
"...faith is the instrument by which we apprehend the righteousness of Christ, or it is the hand with which we receive the righteousness of Christ." [Zacharias Ursinus - Commentary on the Heidelberg]
"QUESTION LXXIII. How doth faith justify a sinner in the sight of God? ANSWER. Faith justifies a sinner in the sight of God; not because of those other graces which do always accompany it, or of good works that are the fruits of it; nor as if the grace of faith, or any act thereof, were imputed to him for his justification; but only as it is an instrument, by which he receiveth and applies Christ and his righteousness." [Thomas Ridgley - WLC - A Body of Divinity]
VI. Justification Distinguished from Sanctification
"Though justification and sanctification are not the same—yet God never pardons a sinner without sanctifying him. Justification and sanctification are not the same. Justification is without us, sanctification is within us. The one is by righteousness imputed, the other is by righteousness imparted. Justification is once and for all, sanctification is gradual." [Thomas Watson - The Lord's Prayer]
"The distinction of both lies herein, that in justification the religious relation of man to God is restored, and in sanctification his nature is renewed and freed from the uncleanness of sin." [Herman Bavinck - Reformed Dogmatics]
"Justification removes the guilt of sin and restores the sinner to all the filial rights involved in his state as a child of God, including an eternal inheritance. Sanctification removes the pollution of sin and renews the sinner ever-increasingly in conformity with the image of God."
"Justification takes place once for all. It is not repeated, neither is it a process; it is complete at once and for all time." [Louis Berkhof - Systematic Theology]