As one contemplates, penetrating deeper and deeper into the nature of reality, one leaves the sensible world behind, transcends the subject/object mode of perception, and experiences one's soul.
Birds inspire and uplift us with their carols... In the muslc of both birds and humans, beauty is "the wine which overflows." When the last lark has fallen silent, something holy will have vanished from the world. The chorus of life will be muted. The cathedral of the earth will have lost its choir.