"To aspire to" means to wish to gain something or to become something better Here the young man and young woman, denied love and emotion in life, seek fulfilment in Eternity As usual in Blake, Heaven is a place of joy and freedom and delight, very different from the usual Christian philosophy of Blake's time http: //www canberra edu au/~ajc/minogue/poetry/blake/sungloss html
To desire with eagerness; to seek to attain something high or great; to pant; to long; followed by to or after, and rarely by at; as, to aspire to a crown; to aspire after immorality
If you aspire to something such as an important job, you have a strong desire to achieve it. people who aspire to public office They aspired to be gentlemen, though they fell far short of the ideal. see also aspiring. to desire and work towards achieving something important aspire to (aspirer, from aspirare , from ad- + spirare )