16 “But the just shall confess to Your Name”. Both when You shall plead their cause, and when You shall maintain their right, they “shall confess to Your Name;” nought shall they attribute to their own merits, all they shall attribute to nought save to Your mercy....Therefore see what follows, see wherewith he concludes. “The upright shall dwell with Your Countenance.” For ill was it with them in their own countenance; well will it be with them with Your Countenance.
For when they loved their own countenance, “In the sweat of their countenance did they eat bread.” Your Countenance shall come to them with abundance to satisfy them. Nought more shall they seek, for nought better have they; no more shall they abandon You, nor be abandoned by You. For after His Resurrection, what was said of the Lord? “You shall fill me with joy with Your Countenance.” Without His Countenance He would not give us joy. For this do we cleanse our countenance, that we may rejoice in His Countenance....Because too, “blessed are the poor in heart, for they shall see God;” He gave the Form of Man both to good and evil, the Form of God He preserved for the pure and good, that we may rejoice in Him, and it may be well with us for ever with His Countenance.
Source: The Enarrations, or Expositions, on the Psalms (New Advent)