'Body is Full of Light' in the Bible

The eye is the lamp of your body. When your eye is clear [spiritually perceptive, focused on God], your whole body also is full of light [benefiting from God’s precepts]. But when it is bad [spiritually blind], your body also is full of darkness [devoid of God’s word].

If, therefore, your whole body is full of light, with no part of it in darkness, it will be entirely illuminated, as when a lamp shines its light on you.”