The Buddha taught that ultimately, the only true and lasting happiness in this world comes from changing our focus from ourselves to others. When we sincerely wish and work for the happiness and benefit of others, we create our own happiness and make our lives truly meaningful.
Shantideva expressed this very well in the Way of the Bodhisattva:
May I become at all times, both now and forever: a protector for those without protection; a guide for those who have lost their way; a ship for those with oceans to cross; a bridge for those with rivers to cross; a sanctuary for those in danger; a lamp for those without light; a place of refuge for those who lack shelter; and a servant to all in need.
source: 2017 New Year Message from the 17th Karmapa Ogyen Trinley Dorje
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