The song she has been singing is 'Oft in the Stilly Night' which tells of a young woman thinking back to her innocent childhood. This has reminded the woman of her own lost innocence and as the title of the painting indicates, she has undergone a crisis of conscience which, since the light symbolises Christ, amounts to a conversion. Hunt in fact stated that the painting was a secular counterpart to his celebrated picture of Christ as 'The Light of the World'. Hunt clearly sees the woman as a victim of the man, their relationship symbolised by the cat playing with the bird under the table. She may well be discarded by him, like the soiled glove in the foreground, in which case her fate would probably be to fall into common prostitution. The callous disregard of the man for his mistress's feelings, or his obtuse lack of awareness of them, is pointed up by Hunt in the Bible quotation on the frame 'As he that taketh away a garment in cold weather, so is he that singeth songs to an heavy heart.' The frame was designed by Hunt, the marigolds are emblems of sorrow, the bells of warning, while the star at the top represents spiritual revelation.
Simon Wilson, Tate Gallery: An Illustrated Companion, Tate Gallery, London, revised edition 1991, p.84