Therefore read these words “me” and “for me” with great emphasis, and accustom yourself to accepting this “me” with a sure faith and applying it to yourself. Do not doubt that you belong to the number of those who speak this “me.” Christ did not love only Peter and Paul and give Himself for them, but the same grace belongs and comes to us as to them; therefore we are included in this “me.” For just as We cannot deny that we are all sinners, and just as we are obliged to say that through his sin Adam destroyed us and made us enemies of God who are liable to God’s wrath and judgment and worthy of eternal death—for all terrified hearts feel and confess this, in fact, more than is proper—so we cannot deny that Christ died for our sins in order that we might be justified. For He did not die to make the righteous righteous; He died to make sinners into righteous men, the friends and sons of God, and heirs of all heavenly gifts. Therefore since I feel and confess that I am a sinner on account of the transgression of Adam, why should I not say that I am righteous on account of the righteousness of Christ, especially when I hear that He loved me and gave Himself for me? Paul believed this most firmly, and therefore he speaks with such πληροφορία [full of assurance].
Martin Luther, Lectures on Galatians (1535) on Galatians 2:21, Luther’s Works 26.179
I so much appreciate Sinclair Ferguson’s sermons on Romans, available on Sermon Audio, where he repeatedly makes the point that, the only people Jesus came to save are sinners, and if you are holding on to any shred of your own righteousness, Jesus is not your Savior. Jesus first makes us righteous through imputing His righteousness to us for our eternal right standing before God, and then by gradually transforming us into His image by the indwelling Holy Spirit, so that we will be personally righteous in the resurrection. Christians have every reason for personal assurance of eternal acceptance with God, it cannot fail, because of this perfect righteousness that is not our own. It is all of grace, for me, that it would be to God’s glory alone.
Despite these words being given ages ago they still speak comfort!