1 John 1:9 (TNTC 1-3 Jn): The proper Christian attitude to sin is not to deny it but to admit it, and then to receive the forgiveness which God has made possible and promises to us. If we confess our sins, acknowledging before God that we are sinners not only by nature (sin) but by practice also (our sins), God will both forgive us our sins and purify us from all unrighteousness. In the first phrase sin is a debt which he remits and in the second a stain which he removes. In both he is said to be faithful and just. The first word may mean that he is faithful to his nature and character (cf. 2 Tim. 2:13). But the faithfulness of God in Scripture is constantly associated with his covenant promises (e.g. Ps. 89; Heb. 10:23). He is true to his word and faithful to his covenant. Since the new covenant includes the pledge, ‘I will forgive their wickedness and will remember their sins no more’ (Jer. 31:34), it is not difficult to see why God is said to be ‘faithful’ in forgiving our sins. But how can he also be described as just when he forgives us our sins? Some commentators relate God’s justice to his faithfulness and suggest that it is by being faithful to his promises that God is just to forgive. Even so it is a strange adjective to use. Justice is associated in our minds with punishment or acquittal, not with forgiveness. If God visits upon the sinner his sin and ‘does not leave the guilty unpunished’ (Exod. 34:7), how can he forgive sins? This is the divine dilemma. The Judge of all the earth cannot lightly remit sin. The cross is, in fact, the only moral ground on which he can forgive sin at all, for there the blood of Jesus his Son was shed that he might be ‘the atoning sacrifice for our sins’ (2:2). Cf. Romans 3:25, another passage in which the justice of God is related to the atoning sacrifice of Christ. So we may say that in forgiving our sins and cleansing us from them, God displays loyalty to his covenant—his faithfulness because of the word which initiated it and his justice because of the deed which ratified it. More simply, he is faithful to forgive because he has promised to do so, and just because his Son died for our sins.
John Stott
Letters to John. 1988
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