The eye receives light from outside and transmits its message inside the person. Jesus said that the eye is like a lamp which shines inwards and the heart is illuminated by what the eye sees. Unhealthy eyes cannot do that. Blind people cannot see where they are or the way ahead. Blurred vision distorts the image and confuses the mind.

But Jesus was using this picture to illustrate spiritual perception. We use the expression, "I see" to mean, "I understand". If we are perceiving truth, then our souls will be free to embrace it and walk in it. If we choose to ignore the truth, then there is no way we can navigate through life and reach eternity safely. The more we block out truth, the deeper our confusion about God and how to live for Him.

There is another meaning here too. The Greek word for 'healthy' also means 'generous', and 'unhealthy' means 'miserly'. Those whose 'eye' is on getting wealth will develop a dark heart, whereas those who love to give to others will have a lightness of heart. That meaning fits well with the preceding verses about storing up treasure for yourselves, and with the following verses about not being able to serve both God and money.

So what fills your soul? Light from God and a desire to live in His love, or the darkness of the world? A lust for wealth, or a love of giving? What we look for shows the state of our hearts. The Lord Jesus wants us to desire what He loves and to focus on what will bless us (Philippians 4:8-9) and to enjoy sharing His truth and material blessings. It is a challenge to be faced today.