DISCERNER, n.

1. One who sees, discovers or distinguishes an observer.
2. One who knows and judges one who has the power of distinguishing.

He was a great observer and discerner of mens natures and humors.

3. That which distinguishes or that which causes to understand.

The word of God is quick and powerful--a discerner of the thoughts and intents of the heart. Hebrews 4 .