Awake to righteousness, and sin not; for some have not the knowledge of God: I speak this to your shame. Awake to righteousness - Shake off your slumber; awake fully, thoroughly, δικαιως, as ye ought to do: so the word should be rendered; not awake to righteousness. Be in earnest; do not trifle with God, your souls, and eternity.
Sin not - For this will lead to the destruction both of body and soul. Life is but a moment; improve it. Heaven has blessings without end.
Some have not the knowledge of God - The original is very emphatic: αγνωσιαν γαρ Θεου τινες εχουσι, some have an ignorance of God; they do not acknowledge God. They have what is their bane; and they have not what would be their happiness and glory. To have an ignorance of God - a sort of substantial darkness, that prevents the light of God from penetrating the soul, is a worse state than to be simply in the dark, or without the Divine knowledge. The apostle probably speaks of those who were once enlightened, had once good morals, but were corrupted by bad company. It was to their shame or reproach that they had left the good way, and were now posting down to the chambers of death.