The poem
When Sorrow, using mine own fire's might, Melts down his lead into my boiling breast, Through that dark furnace to my heart oppressed, There shines a joy from thee, my only light: But soon as thought of thee breeds my delight, And my young soul flutters to thee, his nest, Most rude Despair, my daily unbidden guest, Clips straight my wings, straight wraps me in his night, And makes me then bow down my head and say: "Ah, what doth Phoebus' gold that wretch avail Whom iron doors do keep from use of day?" So strangely (alas) thy works in me prevail, That in my woes for thee thou art my joy, And in my joys for thee my only annoy.