The light of the body is the eye: if therefore thine eye be single, thy whole body shall be full of light. But if thine eye be evil (scattered or unfocused), thy whole body shall be full of darkness. (Matt 6:22-23, KJV)
Is Jesus talking about how the mind works? Is the metaphor of the eye referring to mental focus?
In fact, if the mind is scattered, it loses its ability for clarity, but if the mind is focused (single) it has strength and clarity. This IS how the mind works. (Default Mode Network (ruminating and scattered) vs Task Positive Network (Focused and Attentive)
Whereas most of Christianity sees this saying as “difficult”, it may be because they are trying to draw some sort of moral meaning from it, the actual meaning could be similar to other teachings about how to use the mind properly, and the dangers of letting a scattered mind spin a person around in circles.
In fact the beginning of ruminative vain imaginations, comparisons, sense of unfairness, jealousy, anger, lust, desire, dissatisfaction, all happen in the unfocused ruminating DMN.
Clarity, focus, sense of unity and “home” all reside in the TPN.
Test this hypothesis and see.
Let your mind wander and see where it goes.
Then bring you mind to focus in the breath and the body “present moment” and see where it goes.
Reality is Dharma 