Through service you realize that all beings are waves of the Ocean of Divinity. No other spiritual practice can bring you into the incessant contemplation of the Oneness of all living beings. You feel another's pain as your own; you share another's success as your own. To see everyone else as yourself and yourself in every one is the core of spiritual practice. This spirit makes you humble before the suffering of others. When you rush to render help, you do not calculate how high or low one's social or economic status  is. Thus, the hardest heart is slowly softened into sweetness by the opportunities of service.

- Divine Discourse, Nov 14, 1975.

Love is the solvent for the hardest of the hearts.  Baba