All suffering without exception comes from wishing for one’s own happiness. The perfect Buddhas arise from the altruistic mind. Therefore, completely exchanging one’s own happiness for the suffering of others is the Bodhisattvas’ practice.
A bodhisattva’s practice is to purely exchange
our personal happiness for the suffering of others,
Because (all) our sufferings, without an exception,
Come from desiring our personal happiness,
While a fully enlightened Buddha is born from the attitude
of wishing others well.
– The Berzin Archives Thirty-seven Bodhisattva Practices