For example, lines 2 and 4 should end with an upward inflection because they're questions; but the music makes you want to end them as statements. The "did" in the first line should be stressed as it's part of the tetrameter; but in the hymn the first stress falls on "feet".
Indeed, the first thing to do is say de-DUM de-DUM de-DUM de-DUM a few times as firmly as you can. Then launch in. And DID those FEET in ANCient TIME. It's a completely different poem, postively mooreeffocish.
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 these dark Satanic Mills?
Bring me my Bow of burning gold;
Bring me my Arrows of desire:
Bring me my Spear: O 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
And as a fillip to foreigners here is the hymn accompanied by a series of preposterously patriotic English images that make me tear up and want to jolly well go and shoot a german.
P.S. I was reminded of all this because I went to see the play Jerusalem last night, which is terribly good and goodly terrible.
P.P.S. Anybody who thinks fit to complain about the split infinitive in the last sentence will be fed to the weasels.