Adam and Eve stand together in Eden before the Fall. Twilight is coming on, and Eve is surprised by it. She turns to her husband and she says: "With thee conversing I forget all time" (IV.639). They "talking hand in hand alone" (IV.689) go to their bower. After a moment of spontaneous thanksgiving they enter it and make love:

"Handed they went; and eas'd the putting off
These troublesom disguises which wee wear,
Strait side by side were laid, nor turnd I weene
Adam from his fair Spouse, nor Eve the Rites
Mysterious of connubial Love refus'd." (IV.739-43)

Every one of these actions makes up a part of their conversation together – a word of great importance to Milton, used across its whole range of meaning to express mutual intimacy of every kind. Unlike their fallen children, Adam and Eve don't need to waste time taking off their clothes ("these troublesom disguises") – nor, by extension, have they to drop any defensive social mask unmeet for love. Not until after the Fall will Eve put on a face for Adam which is not nakedly her own (IX.853-5).

This is the "conversing" relationship Milton sets up against Satan's self-willed isolation. Adam and Eve are ideal embodiments of human qualities which are, for Milton, both sacred and divine – loving intimacy, mutual responsibility, a sacrificial regard for the common weal. But since he sees Adam and Eve as inhabiting those qualities rather than as creating them, Milton needs to do something else as well. He needs to express God, within the epic narrative, as ultimate author of all that is good in human flourishing and circumstance. He needs to bring him on, in that role, as a character. And he must fail at it (VII.18-19). God will not be comprehended by one of his creatures, and he certainly is not going to fit into the space left for the gods in classical epic. Yet that is what is available for him – a place formerly held by Jupiter, that arbitrarily powerful superbeing with his inexplicable fits of temper and/or passion, with his fragile celebrity ego.

So Milton has an insoluble difficulty, which is partly philosophical but is literary too. He fails better, though, than he is often given credit for. Mostly God in Paradise Lost is prudently refracted through the eyes of another character, and often that character reminds his hearers that he is reducing for intelligibility. "How shall I relate," asks Raphael the angel as he introduces the war in heaven, "to human sense th'invisible exploits/Of warring Spirits"? (V.564-5). God as inexpressible mystery, as beyond all human categories, must be delineated indirectly. But twice God appears in person without a filter: once when he speaks with Adam and Eve after their Fall, at the opening of Book X, and once, most significantly, in conversation with himself, during the first half of Book III.

Satan has just flown past on his way to earth and suddenly we are in heaven watching him go, along with God, who in the forced perspective of epic must laboriously explain to us what he omnisciently knows and what he is omnipotently going to do about it. This section is, in the whole poem, the one closest to justifying God's ways – and, from that point of view, is also the one least like a good poem. Parts of it – like the moment when God points out that his foreknowledge of the angels' fall cannot, logically speaking, take away their free will (III.117-9) – afford all the emotional satisfaction of a game of solitaire on a rainy Sunday afternoon.

But there is more to the conversation than God the Father fighting his theological corner in a hostile cosmic seminar. Milton's God is Trinitarian – Father, Son and Holy Spirit, three Persons in one God – and so his conversation expresses relationship within and between himself. God the Father takes upon him the facet of justice, God the Son that of mercy. But they aren't two different people, they are still one entity wrestling with qualities they possess together. We are invited to witness God working out upon himself a deep difficulty – how to bring mercy into the operation of justice, justice into the outflowing of forgiveness (III.406-7).

God the Father, talking the two into balance, topples into forgiveness – "Mercy first and last shall brightest shine" (III.134). God the Son picks up the thought and runs with it, pointing out that anything but mercy will show God unjust to his ill-defended creation (III.165-6). But how, asks God the Father, can man be freed from the ultimate selfishness of usurping divinity? "Die hee or Justice must" (III.210). All right, says the Son, then Justice must die. He means personified Justice. He means himself. God must self-forget and become man, must as man suffer every degrading humiliation man can visit upon his fellows, and finally must be killed so that humanity might live godlike after all:

"His words here ended, but his meek aspect
Silent yet spake, and breath'd immortal love
To mortal men, above which only shone
Filial obedience: as a sacrifice
Glad to be offer'd, he attends the will
Of his great Father." (III.266-71)

Looking towards that great turn, the redemption of humanity for divine love the angels sing God's praises. They start with what they cannot express, using sublime negatives and deliberate paradox: "Immutable, Immortal, Infinite … Fountain of Light, thyself invisible" (III.373-5). This is the God Milton can't turn into a character, "Thron'd inaccessible" (III.377). But he is also the "conspicuous countenance" of the human face divine, the Son "without cloud/made visible" (III.385-6). God's story becomes a human one.

Milton is not going to tell that story. He had tried once as a young man – in his unfinished poem The Passion – and hadn't been able to go on. He won't try again – his late poem Paradise Regained is about Christ's temptation, not about his death. But we may expect Adam and Eve, the humans of the story he does tell, to find their redemption in acts of love and sacrifice. And that, in tragic mode, is what we will get.

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