This beautiful promise near the end of the book of Malachi was for those who felt convicted of their disrespect for God and who signed the "scroll of remembrance" to recommit themselves to God. Righteousness would rise up to shine on them like the rays of the sun. And in those rays they would find healing.
We might reasonably ask what sort of healing Malachi had in mind. Malachi talks again about the last days when the world will be purified as with fire. He had pointed out that no one was safe from God's refining fire (Malachi 3:2-3). In other words, we are all sinners. The difference is that those who live in humble repentance for the sin that makes them distant from God will be forgiven of their sins. Those who will not fear God will be consumed as in a fire that burns everything completely.
Just as those who signed the scroll of remembrance in Malachi's day, we too have the opportunity to commit or recommit ourselves to God. If we can accept and repent of our own sin and imperfection, the hurts we have caused others, and the distance our sin has created between ourselves and God, then God's righteousness will rise like the sun on us as well.
Dear Jesus, you rose from the dead and shined your righteousness on me. I know that you have paid for my sins. Please accept my prayer and help me to commit my life to you. Amen.