Shortly after Jesus taught His disciples how to pray,1 He proceeded to speak about light in three short sayings. He started with a reference to physical light, and then moved on to speak of the light that is within us.
No one lights a lamp and then hides it or puts it under a basket. Instead, a lamp is placed on a stand, where its light can be seen by all who enter the house.2
The lamp spoken of could either be a lamp with a candlestick inside it or an oil-burning lamp, the latter being more likely. It would make no sense to light a lamp and then put it in a place where its light would serve no purpose and no one would benefit from it.
Jesus and His message are associated with light throughout the Gospels.
The Word gave life to everything that was created, and his life brought light to everyone.3
Elsewhere in the New Testament we read of light in reference to those who believe in Jesus.
Once you were full of darkness, but now you have light from the Lord. So live as people of light!4
Jesus and His message—the Light—are not to be hidden. They are to be widely proclaimed through His ministry, through His disciples, and through believers across time. If the message is rejected by some, it’s not because it’s a hidden or secret teaching; it’s that after hearing the message, the hearer has chosen to reject it.
Jesus followed with the second saying:
Your eye is like a lamp that provides light for your body. When your eye is healthy, your whole body is filled with light. But when it is unhealthy, your body is filled with darkness.5
According to medical understanding in ancient times, the eyes didn’t allow light to come in, but rather people had light within them and this light came out of their eyes, which caused them to see. Jesus’ saying reflects this ancient concept. The hearers would have understood that Jesus was referring to the eyes as the source of light emanating from the body, which could be either healthy or unhealthy. If the eye is healthy, it indicates that the person is inwardly full of light, which the eye is emitting. However, if the eye is unhealthy and thus not emitting light, it shows that the person is full of darkness.
Jesus was speaking about a person’s inner self, their spiritual condition. If the eye wasn’t healthy, then the inner being of the person was dark, without any spiritual light—they were morally unhealthy. The healthy eye is understood as belonging to one who is focused on the good, whom God has filled with light.
You, Lord, keep my lamp burning; my God turns my darkness into light.6
The people who rejected Jesus’ message were those whose eye—their inner self—was full of darkness. Jesus then warned:
Make sure that the light you think you have is not actually darkness. If you are filled with light, with no dark corners, then your whole life will be radiant, as though a floodlight were filling you with light.7
He stated that the things which guide one’s thoughts, life, decision-making, etc., need to come from the light; and therefore, people need to do all they can to watch that the light within them is true light, that they are spiritually healthy.
The light inside of believers will shine out, like a lamp that is lit. Those who believe in Him and His teachings, without any hardness of heart, are inwardly spiritually healthy, full of light. They will shine with Jesus’ light in the same way someone in a dark room stands out when a light is shining on them.
There seems to be a progression in these three verses. Jesus is the light, placed where all can see. A person’s spiritual health is determined by their response to the light. Those who take in Jesus’ light will be spiritually healthy, and as such they will brightly shine and give off light. They will reflect the light of Jesus to others through the way they live and the love they show. This is contrasted with those who reject Jesus, whose eye is bad and therefore are full of darkness. The message is to embrace the light, to believe in Jesus. Those who have light within are able to be guided by God, make right choices, and be His light to others.