Passage
For thou art my lamp, O Jehovah; And Jehovah will lighten my darkness.
For thou art my lamp, O Jehovah; And Jehovah will lighten my darkness.
2 Samuel 22:27 With the pure thou wilt show thyself pure; And with the perverse thou wilt show thyself froward.
2 Samuel 22:28 And the afflicted people thou wilt save; But thine eyes are upon the haughty, that thou mayest bring them down.
2 Samuel 22:29 For thou art my lamp, O Jehovah; And Jehovah will lighten my darkness.
2 Samuel 22:30 For by thee I run upon a troop; By my God do I leap over a wall.
2 Samuel 22:31 As for God, his way is perfect: The word of Jehovah is tried; He is a shield unto all them that take refuge in him.
The verse centers on "light", "darkness", "thou", "lamp", "jehovah", and "lighten". It is saying that the contrast between light and darkness marks a real divide in how people respond to God's work.
The nearby context moves from verse 28's "And the afflicted people thou wilt save..." into verse 30's "For by thee I run upon a...", so "light" and "darkness" belong inside that flow. In 2 Samuel context, the local focus is covenant, worship, and faithfulness.
A plain takeaway is to answer the verse's own emphasis on "light" and "darkness" with trust shaped by these words, not by a vague optimism outside the passage.