Believers are light in the Lord
2 Corinthians 4:6 (ASV)
6Seeing it is God, that said, Light shall shine out of darkness, who shined in our hearts, to give the light of the knowledge of the glory of God in the face of Jesus Christ.
Ephesians 5:8 (ASV)
8for ye were once darkness, but are now light in the Lord: walk as children of light