Passage
With the merciful thou wilt show thyself merciful; With the perfect man thou wilt show thyself perfect;
With the merciful thou wilt show thyself merciful; With the perfect man thou wilt show thyself perfect;
2 Samuel 22:24 I was also perfect toward him; And I kept myself from mine iniquity.
2 Samuel 22:25 Therefore hath Jehovah recompensed me according to my righteousness, According to my cleanness in his eyesight.
2 Samuel 22:26 With the merciful thou wilt show thyself merciful; With the perfect man thou wilt show thyself perfect;
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.
The verse centers on "merciful", "thou", "wilt", "show", "thyself", and "perfect". It is saying that the verse draws attention to "merciful" and "thou", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 25's "Therefore hath Jehovah recompensed me according to..." into verse 27's "With the pure thou wilt show thyself...", so "merciful" and "thou" 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 "merciful" and "thou" with trust shaped by these words, not by a vague optimism outside the passage.