From The Path of Light, by Santideva, c. 700 CE
May I become a medicine for a sick and their physician, their support until sickness come not again.
May I become an unfailing store for the wretched, and be first to supply them with their needs.
My own self and my pleasures, my righteous past, present and future, may I sacrifice without regard, in order to achieve the welfare of beings.
The Oxford Book of Prayer, ed. Appleton, p. 309