For God, who commanded the light to shine out of darkness. — Better, For it is God who commanded... that hath shined. The whole verse is in manifest antithesis to 2 Corinthians 4:4. The god of this world did his work of blinding; the true God called light out of darkness. Here there is obviously a reference to the history of the creation in Genesis 1:3.
Hath shined. — The English tense is allowable, but the Greek is literally shone, as referring to a definite fact in the past life of the Apostle and other Christians at the very time of their conversion.
In the face of Jesus Christ. — Some MSS. give “Christ Jesus,” others “Christ.” The clause is added as emphasising the fact that the glory of God is for us manifested only in the face (or, possibly, in the person, with a somewhat wider sense; see Note on 2 Corinthians 1:11) of Christ, as it was seen by the Israelites in the face of Moses. The word for “give light” is the same as that rendered “radiance” in 2 Corinthians 4:4.