And did those feet in ancient time

"Jerusalem" is a short poem by William Blake from the preface to his epic Milton a Poem, one of a collection of writings known as the Prophetic Books. The date of 1804 on the title page is probably when the plates were begun, but the poem was printed c. 1808. Today it is best known as the anthem "Jerusalem", with music written by Sir Hubert Parry in 1916. It is not to be confused with another poem, much longer and larger in scope, but also by Blake, called Jerusalem The Emanation of the Giant Albion.

The poem was inspired by the apocryphal story that a young Jesus, accompanied by Joseph of Arimathea, a tin merchant, travelled to what is now England and visited Glastonbury during his unknown years. The poem's theme is linked to the Book of Revelation (3:12 and 21:2) describing a Second Coming, wherein Jesus establishes a New Jerusalem. The Christian church in general, and the English Church in particular, has long used Jerusalem as a metaphor for Heaven, a place of universal love and peace.

In the most common interpretation of the poem, Blake implies that a visit by Jesus would briefly create heaven in England, in contrast to the "dark Satanic Mills" of the Industrial Revolution. Blake's poem asks four questions rather than asserting the historical truth of Christ's visit. Thus the poem merely implies that there may, or may not, have been a divine visit, when there was briefly heaven in England.

The original text is found in the preface Blake wrote for inclusion with Milton, a Poem, following the lines beginning "The Stolen and Perverted Writings of Homer & Ovid: of Plato & Cicero, which all Men ought to contemn: ..."

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