Proverbs 15:30 The light of the eyes rejoiceth the heart: and a good report maketh the bones fat.
God promises that Christians will have a positive effect on other people around us in the world. Jesus says that we are the salt of the earth and the light of the world. Here the proverb says that our very presence and appearance brings joy to the souls of people, and our words and speech give health to the bodies of people. This is true and it happens even when we don’t see the effects. We must believe that our lives, our living on earth, our words and our very presence makes a difference.
The positive effect of our lives on those around us is not something we can make happen by effort. We cannot just decide we are going to start making others happy and healthy. We are not commanded to be salt and light; we are. How we live and what we say comes out of who we are. We are new persons with a new life inside, and it comes out in the eyes and the words. Our job is to focus in the Cross, listen to the Word, hear the Gospel, remember our Baptism, repent and believe daily. Then our eyes and mouth show it.
Unfortunately, of course, we are still sinners, living in sinful, selfish flesh. And this nature comes out of us at the same time. “Out of the heart proceeds” all kinds of sin and evil. So says Jesus. The eyes are filled with sadness and anger; the mouth gives a bad report with gossip and judgmental words. We still bring others down and negatively affect their health. That is why we repent daily and fill the heart with the gospel of Christ.
Then we live our lives, trusting the promise that Jesus comes out naturally. This happens when we focus on Jesus instead of on self. And we believe the promise that it works. The eye is the “lamp of the body” and brings joy. A good news report brings health. In the Bible “fatness of bones” is a good thing, signifying health. We have the privilege of making people feel better in body and soul.