King James Bible
"The light of the body is the eye: if therefore thine eye be single, thy whole body shall be full of light."
Jesus identifies the eye as the body's lamp, drawing on ancient understanding that eyes were thought to emit light enabling vision. This metaphor establishes that spiritual perception determines one's inner illumination, with the eye representing the soul's capacity to receive and focus on truth. The Greek word for 'single' (haplous) means simple, clear, or generous—contrasting with an evil or stingy eye. In Jewish thought, a 'single eye' indicated moral clarity and undivided devotion, particularly in the context of generosity versus greed that frames this passage. When one's spiritual vision remains focused and pure, the entire person experiences divine illumination. This promise connects to the surrounding teachings on treasures and masters, suggesting that singular devotion to God floods one's whole being with spiritual understanding and life.