Donald Macleod on how repentance and conversion do not atone for our sins.
Yet it is never the cross, in and of itself, which evokes repentance, and this highlights another weakness of the rectoral [governmental] theory. It bypasses the ministry of the Holy Spirit. He alone can produce repentance, and the repentance he produces is not the cause of the atonement, but its consequence. The cross, resurrection and ascension of Jesus secure the ministry of the Spirit, with all the gifts and blessings which that brings with it. Foremost among these is the gift of repentance; never a human achievement, but a divine given (Acts 5:31), produced not by mere demonstration, but by the intimate touch of grace in the depths of the human heart.
This touch, of course, produces its own psychological narrative as the sinner faces the truth about himself, accepts that his life is indefensible and acquiesces unquestioningly the judgment of God (Psalm 51:1-4). The cross may be one of the cognitive elements in this journey. It may highlight the ugliness of sin. It may bespeak God’s abhorrence of it. It may make us ashamed of our past attitudes to Christ. It may fill us with wondering appreciation of the love of God. But none of these is what constitutes atonement or purchases redemption. Instead, in the language of the older evangelical piety, repentance is itself a ‘blood-bought’ grace, created in our hearts by the mysterious agency of the Holy Spirit. The psychological journey which marks a sinner’s recovery is but the outward expression of the inner touch of the supernatural. Yet the real foundation of assurance and joy is the knowledge that whatever the shortcomings of our repentance (or of our conversion-narrative) God accepts us for Jesus’ sake.
This may seem like an obvious point, but we often look at the sincerity of our repentance as the ground for our salvation. Did I repent enough? Was my conversion really real? Did my heart really change? And so on. There is a place for self-examination, but assurance must be found in Christ, not in how awesome our conversion was, how much we hated our sins, or how sincere our repentance was.