Joy is itinerant and can be visited in many places, but its regular venue is friendship. Friendship is the love of difference. The face of the friend is the mirror in which the joy of one’s own difference shines.
The subjective precondition for joy is not earnestness or sentimentality (much less a vaguely pious posture of generic ‘openness’), but attention. Attention is the discipline of active passivity, an intense concentration on what is there. It is what Simone Weil calls ‘waiting’: ‘We do not obtain the most precious gifts by going in search of them but by waiting for them [attendus].’ This is why Paul speaks of joy not as aesthetics but as ethics. Writing to the Philippians in the chains of Christ, he subjects them to a moral imperative: ‘Rejoice!’