After creating the heaven and the earth, though whilst the latter was still ‘without form, and void’, God’s first creative act, according to Genesis, and the most sublime passage in the Bible, according to Longinus, is the performative utterance ‘Let there be light’ (Genesis, 1:3). 1 If, as Aquinas argues, God may be known analogically, as a cause may be known from its effects, 2 light would seem to hold a privileged place in any attempt to know and approach God, since, after the heaven and the formless earth, it is the first of these divine effects, and also because it permits the apprehension of most of the others. 3 Yet, as the Bible also tells us, light may paradoxically impede our knowledge of God, even as it simultaneously permits it; as Paul writes, ‘the King of kings, and Lord of lords’ dwells ‘in the light which no man can approach unto’ (1 Timothy, 6:15–16). This paradoxical conception of light, as concealing the God that it also reveals, is central to Milton’s presentation of the Divine in Paradise Lost – which, alluding to both John and Paul, maintains that ‘God is light / And never but in unapproached light / Dwelt from Eternitie’ (III, 3–4) 4 – and may, I wish to suggest in this chapter, help us to understand the Romantic visionary.