Those who, so far as it is possible, engage in the work of doing good to others by giving practical demonstration of their interest in them, are not only relieving the ills of human life in helping them bear their burdens, but are at the same time contributing largely to their own health of soul and body. Doing good is a work that benefits both giver and receiver. If you forget self in your interest for others, you gain a victory over your infirmities. The satisfaction you will realize in doing good will aid you greatly in the recovery of the healthy tone of the imagination.
(MYP 209.1)
The pleasure of doing good animates the mind and vibrates through the whole body. While the faces of benevolent men are lighted up with cheerfulness, and their countenances express the moral elevation of the mind, those of selfish, stingy men are dejected, cast down, and gloomy. Their moral defects are seen in their countenances. Selfishness and self-love stamp their own image upon the outward man.
(MYP 209.2)
That person who is actuated by true disinterested benevolence is a partaker of the divine nature, having escaped the corruption that is in the world through lust; while the selfish and avaricious have cherished their selfishness until it has withered their social sympathies, and their countenances reflect the image of the fallen foe rather than that of purity and holiness.—Testimonies for the Church 2:534.
(MYP 209.3)