From the writings of Saint John of Capistrano.
Those who are called to the table of the Lord must glow with the brightness that comes from the good example of a praiseworthy and blameless life. They must completely remove from their lives the filth and uncleanness of vice. Their upright lives must make them like the salt of the earth for themselves and for the rest of mankind. The brightness of their wisdom must make them like the light of the world that brings light to others. They must learn from their eminent teacher, Jesus Christ, what he declared not only to his apostles and disciples, but also to all the priests and clerics who were to succeed them, when He said, “You are the salt of the earth. But what is salt goes flat? How can you restore its flavor? Then it is good for nothing but to be thrown out and trampled underfoot.” Jesus also said: “You are the light of the world.” Now a light does not illumine itself, but instead it diffuses its rays and shines all around upon everything that comes into its view. So it must be with the glowing lives of upright and holy clerics. By the brightness of their holiness they must bring light and serenity to all who gaze upon them. They have been placed here to care for others. Their own lives should be an example to others, showing how they must live in the house of the Lord.