The “blackness” (KJV, ASV) of course, is not the pigmentation of her skin but the exposure to the hot Middle-Eastern sun; it is color, not race that is in view. She had been under the authority of her angry brothers, keeping their vineyards, and she had neglected herself. Despite the consciousness and insecurity of a weather-beaten appearance (“very dark” ESV) and personal unattractiveness, however, the Shulamite is confident that she had not lost her beauty. She had a history, for sure, and carried a lot of baggage. She had made mistakes and had regrets, but there was a beauty from which all of this could not detract.
Only self-righteousness is unconscious of sin, but the righteousness of God brings personal insecurity and divine confidence simultaneously (Philippians 3:9 cf. 2 Corinthians 7:10). The truth is, I see myself in her. I am a miserable sinner, with baggage and regrets, and continually tripping over my own remaining corruption. However, I am confidently falling into the tender and gracious arms of a loving Savior who is “faithful and just to forgive us our sins …” (1 John 1:9).
I live continually with these two realities. Luther’s term for this was “Armer Sunder Christentum”—miserable sinner Christianity. In other words, the Christian is perpetually a penitent sinner. The Christian is totally depraved—and feels it—but he/she rests on the Savior’s absolute sufficiency.