Our justification is the direct result of our believing the gospel; our knowledge of our own justification comes from believing God’s promise of justification to every one who believes these glad tidings. For there is not only the divine testimony, but there is the promise annexed to it, assuring eternal life to every one who receives that testimony. There is first, then, a believed gospel, and then there is a believed promise. The latter is the “appropriation,” as it is called; which, after all, is nothing but the acceptance of the promise which is everywhere coupled with the gospel message. The believed gospel saves; but it is the believed promise that assures us of this salvation.
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Faith is not Christ, nor the cross of Christ. Faith is not the blood, nor the sacrifice; it is not the altar, nor the laver, nor the mercy-seat, nor the incense. It does not work, but accepts a work done ages ago; it does not wash, but leads us to the fountain opened for sin and uncleanness. It does not create; it merely links us to that new thing which was created when the “everlasting righteousness” was brought in (Daniel 9:24).
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Though faith is not “the righteousness,” it is the tie between it and us. It realizes our present standing before God in the excellency of His own Son; and it tells us that our eternal standing, in the ages to come, is in the same excellency, and depends on the perpetuity of that righteousness which can never change. For never shall we put off that Christ whom we put on when we believed (Romans 12:14; Galatians 3:27). This divine raiment is “to everlasting.” It waxes not old, it cannot be rent, and its beauty fadeth not away.
—Horatius Bonar
The Everlasting Righteousness, Chapter 7