13 “There has fallen upon them fire, and they have not seen the sun.” You see in what manner he speaks of a certain punishment of darkening. “Fire has fallen upon them,” fire of pride, a smoky fire, fire of lust, fire of wrath. How great a fire is it? He upon whom it shall have fallen, shall not see the sun. Therefore has it been said, “Let not the sun go down upon your wrath.” Therefore, brethren, fire of evil lust fear ye, if you will not melt like wax, and to perish from the face of God. For there falls upon you that fire, and the sun you shall not see. What sun? Not that which together with you see both beasts and insects, and good men and evil men: because “He makes His sun to rise upon good men and evil men.” But there is another sun, whereof those men are to speak, “And the sun has not risen to us, passed away are all those things as it were a shadow. Therefore we have strayed from the way of truth, and the light of righteousness has not shone to us, and the sun has not risen to us.”...
Source: The Enarrations, or Expositions, on the Psalms (New Advent)