I love this hymn.
It is based on a poem by William Blake, and was adapted to music by Sir Hubert Parry. The most well-known arrangement/orchestration is by Edward Elgar.
Lyrics:
And did those feet in ancient time
Walk upon England’s mountains green?
And was the Holy Lamb of God
On England’s pleasant pastures seen?
And did the Countenance Divine
Shine forth upon our clouded hills?
And was Jerusalem builded here
Among those dark Satanic Mills?
Bring me my bow of burning gold!
Bring me my arrows of desire!
Bring me my spear! Oh Clouds unfold!
Bring me my chariot of fire!
I will not cease from mental fight
Nor shall my sword sleep in my hand
Till we have built Jerusalem
In England’s green and pleasant land!