Joy is as joy does

"Perhaps surprisingly, another important aspect of equanimity is joy. Recognizing the joy of equanimity goes across the common view that equanimity is dry, unemotional, and somewhat aloof. For the Buddha, however, mature equanimity is linked with a deep and sometimes subtle joy and happiness, characteristic of a (relative) freedom of mind and heart. Joy naturally arises, the Buddha tells us, when we no longer are hooked by what is agreeable or disagreeable in experience. As we work through our attachments and aversions, we become more and more "purified and bright, malleable, wieldy, and radiant," "peaceful" and "sublime."