The Following quotations come from B. B. Warfield’s magisterial essay “Faith” originally written for the Hastings Dictionary of the Bible (1905). This article was reprinted in volume 2 of The Works of Benjamin B. Warfield, “Biblical Doctrines” (467-508). Warfield’s essay can be found here in its entirety: The Biblical Doctrine of Faith. Well worth a read.
I’ve taken a number of citations from Warfield’s essay and included the page numbers from the Biblical Doctrines volume.
The saving power of faith resides thus not in itself, but in the Almighty Saviour on whom it rests. It is never on account of its formal nature as a psychic act that faith is conceived in Scripture to be saving,—as if this frame of mind or attitude of heart were itself a virtue with claims on God for reward, or at least especially pleasing to Him (either in its nature or as an act of obedience) and thus predisposing Him to favour, or as if it brought the soul into an attitude of receptivity or of sympathy with God, or opened a channel of communication from Him. It is not faith that saves, but faith in Jesus Christ: faith in any other saviour, or in this or that philosophy or human conceit (Col. 2:16, 18, 1 Tim. 4:1), or in any other gospel than that of Jesus Christ and Him as crucified (Gal. 1:8, 9), brings not salvation but a curse. It is not, strictly speaking, even faith in Christ that saves, but Christ that saves through faith. The saving power resides exclusively, not in the act of faith or the attitude of faith or the nature of faith, but in the object of faith; and in this the whole biblical representation centres, so that we could not more radically misconceive it than by transferring to faith even the smallest fraction of that saving energy which is attributed in the Scriptures solely to Christ Himself. (504)
So little indeed is faith conceived as containing in itself the energy or ground of salvation, that it is consistently represented as, in its origin, itself a gratuity from God in the prosecution of His saving work. It comes, not of one’s own strength or virtue, but only to those who are chosen of God for its reception (2 Thess. 2:13), and hence is His gift (Eph. 6:23, cf. 2:8, 9, Phil. 1:29), through Christ (Acts 3:16, Phil. 1:29, 1 Pet. 1:21, cf. Heb. 12:2), by the Spirit (2 Cor. 4:13, Gal. 5:5), by means of the preached word (Rom. 10:17, Gal. 3:2, 5); and as it is thus obtained from God (2 Pet. 1:1, Jude 3, 1 Pet. 1:21), thanks are to be returned to God for it (Col. 1:4, 2 Thess. 1:3). Thus, even here all boasting is excluded, and salvation is conceived in all its elements as the pure product of unalloyed grace, issuing not from, but in, good works (Eph. 2:8–12). The place of faith in the process of salvation, as biblically conceived, could scarcely, therefore, be better described than by the use of the scholastic term ‘instrumental cause.’ Not in one portion of the Scriptures alone, but throughout their whole extent, it is conceived as a boon from above which comes to men, no doubt through the channels of their own activities, but not as if it were an effect of their energies, but rather, as it has been finely phrased, as a gift which God lays in the lap of the soul. (505)
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