In the Sermon on the Mount, Jesus encourages his disciples to put the Beatitudes into practice and become salt of the world and light for others. Salt is an ingredient that gives flavor to food and also preserves the food from getting spoiled. When salt remains unused for a considerable amount of time, it loses its taste and becomes useless for flavoring.

Similarly, the life of a Christian that remains centered unto itself becomes tepid and bland. Just as “salt does not flavor itself,” so also a Christian ought not to “preserve himself,” but instead “be salt in order to give.”

In the book of Revelation, the glorious Christ warns the Church in Laodicea that has become inactive and tepid in faith, “Because you are lukewarm, neither hot nor cold, I will spit you out of my mouth” (3:16). And in order that the disciples’ faith may maintain its savor, they have to be connected to the source of life-giving dynamism and zest through “prayer to God.” Prayer is the “battery” that adds life, counteracts the contagion of sin, and preserves the faithful from spiritual dryness and aridity.

Secondly, Jesus urges his disciple to be the “light of the world” patterned after their Master who is the true “light of the world” (Jn 9:5). The light of faith that they have obtained from Jesus must be passed on to others. It is not enough to confess the faith, one must live the faith.

In concrete terms, Isaiah describes the “man of light”: “If you remove the yoke from among you, the accusing finger, and malicious speech; if you lavish your food on the hungry and satisfy the afflicted; then your light shall rise in the darkness, and your gloom shall become like midday” (Is 58:9-10).

Pope Francis explains the meaning of the images of salt and light: “We who are baptized Christians are missionary disciples and we are called to become a living Gospel in the world: with a holy life we will ‘flavor’ different environments and defend them from decay, as salt does; and we will carry the light of Christ through the witness of genuine charity. But if we Christians lose this flavor and do not live as salt and light, we lose our effectiveness. This mission of giving light to the world is so beautiful! We have this mission, and it is beautiful! It is also beautiful to keep the light we have received from Jesus, protecting it and safeguarding it.

The Christian should be a luminous person; one who brings light, who always gives off light! A light that is not his, but a gift from God, a gift from Jesus. We carry this light. If a Christian extinguishes this light, his life has no meaning: he is a Christian by name only, who does not carry light; his life has no meaning. I would like to ask you now, how do you want to live? As a lamp that is burning or one that is not? Burning or not? How would you like to live? [The people respond: Burning!] As burning lamps! It is truly God who gives us this light and we must give it to others. Shining lamps! This is the Christian vocation” (May 23, 2013).