Sympathetic joy is a sincere pleasure, untainted by jealousy or a sense of competition, at the happiness and prosperity that others have. It also involves the cultivation of the excellent thought “How wonderful it would be if all beings had perfect prosperity and well-being!” It is a sense of delight that, due to their past karma, beings have attained happiness, and gives rise to the wish that they will never lose their contentment and bliss.
Jigmed Lingpa