NET
6 For God, who said “Let light shine out of darkness,” is the one who shined in our hearts to give us the light of the glorious knowledge of God in the face of Christ.
Darby
6 Because [it is] the God who spoke that out of darkness light should shine who has shone in our hearts for the shining forth of the knowledge of the glory of God in [the] face of [Jesus] Christ.
KJV
6 For God, who commanded the light to shine out of darkness, hath shined in our hearts, to [give] the light of the knowledge of the glory of God in the face of Jesus Christ.