You cannot claim a man is an alchemist and fail to lay out the gold. This, then, is an undated poem, probably written for the woman he married, Anne More, some time in his 20s, known as “Love’s Growth” –

I scarce believe my love to be so pure
As I had thought it was,
Because it doth endure
Vicissitude and season as the grass;
Methinks I lied all Winter, when I swore
My love was infinite, if Spring make’t more.

But if this med’cine, love, which cures all sorrow
With more, not only be no quìntes sence,
But mixed of all stuffs paining soul or sense,
And of the Sun his working vigour borrow,
Love’s not so pure and abstract as they use
To say, which have no mistress but their Muse;
But, as all else being elemented too,
Love sometimes would contèmplate, sometimes do.
And yet not greater, but more eminent,
Love by the Spring is grown,
As in the firmament
Stars by the Sun are not enlarged but shown.
Gentle love-deeds, as blossoms on a bough,
From love’s awakened root do bud out now.

If as in water stirred more circles be
Produced by one, love such additions take;
Those, like to many spheres, but one heaven make,
For they are all concentric unto thee;
And though each Spring do add to love new heat –
As princes do in times of action get
New taxes, and remit them not in peace –
No winter shall abate the spring’s increase.

Read the opening stanza and all the oxygen in a five-mile radius rushes to greet you. It’s a poem with gleeful tricks and puns in it. “But if this med’cine, love, which cures all sorrow/ With more” is a small, private gift for Anne More.

Donne baked the idea of time’s accumulation and love’s accumulation with it into the structure of the poem. Twenty-four 10-syllable lines, plus four of six (equalling 24): the hours in the day. Seven rhymes per stanza: the days in the week. Twenty-eight lines in the poem: the days in a lunar month, each day part of love’s growth.

Love, he writes, is a mixture of elemental things: “as all else being elemented too” – and so “love sometimes would contemplate, sometimes do”. Donne is more daring than he sounds: the 13th-century theologian Thomas Aquinas’s ideal was the “Mixed Life”, one of contemplation and action. Donne hijacks the Aquinian ideal and turns it to his own erotic purpose: the “do” is sex. It’s the same impulse as in another poem, “The Ecstasy”, where bodies must join as well as minds, “else a great prince in prison lies”. True sex, he insists, is soul played out in flesh.

“Love’s Growth” hangs on the idea of apparently infinite love, made more – which, once you have read all that he wrote, is wholly unsurprising. Donne was an infinity merchant; the word is everywhere in his work. More than infinity: super-infinity.

A few years before his own death, Donne preached a funeral sermon for the poet George Herbert’s mother Magdalen, who would “dwell bodily with that righteousness, in these new heavens and new earth, for ever and ever and ever, and infinite and super-infinite forevers”. In a different sermon, he wrote of how we would one day be with God in “an infinite, a super-infinite, an unimaginable space, millions of millions of unimaginable spaces in heaven”. He loved to coin formations with the super- prefix: super-edifications, super-exaltation, super-dying, super-universal, super-miraculous. It was part of his bid to invent a language that would reach beyond language, because infinite wasn’t enough.

That version of Donne – excessive, hungry, longing – is everywhere in the love poetry. Sometimes it was worn lightly: who has yet written about nudity with more glee, more jokes? Then there is the wilder, defiantly odd Donne, typified by the poem for which most people know him, “The Flea”. The speaker watches a flea crawl over the body of the woman he desires:

Mark but this flea, and mark in this
How little that which thou deny’st me is;
Me it sucked first, and now sucks thee,
And in this flea, our two bloods mingled be.

When the poem was first printed in 1633, the typographers used the “long s”, a letter that looks almost identical to an f, for the words “sucked” and “suck”: which offers readers of the third line another, more extravagant rendering.

There is the meat and madness of sex in his work – but, more: Donne’s poetry believed in finding eternity through the human body of one other person. It becomes akin to sacrament. Sacramentum is the translation in the Latin Bible for the Greek word for mystery: and Donne knew it when he wrote, “We die and rise the same, and prove/ Mysterious by this love.” He knew awe: “All measure, and all language, I should pass/ Should I tell what a miracle she was.” And in “The Ecstasy”, love is both a mystery and its solution. He needed to invent a word, “unperplex”, to explain:

“This ecstasy doth unperplex,”
We said, “and tell us what we love…”
But as all several souls contain
Mixture of things, they know not what,
Love these mixed souls doth mix again,
And makes both one, each this and that.

“Each this and that”: his work suggests that we might voyage beyond the blunt realities of male and female. In “The Undertaking”, probably written around the time he met Anne, the body can take you to a place of merging:

If, as I have, you also do
Virtue attired in woman see,
And dare love that, and say so too,
And forget the “he” and “she”…

His poetry sliced through the gender binary and left it gasping on the floor. It’s in “The Relic”, too: “diff’rence of sex no more we knew/ Than our guardian angels do” – for angels were believed to have no need of gender. He offered the possibility of sex as transformation: and we are more tempted to believe him when he says it, because he is the same man who acknowledges, elsewhere, feverishness, disappointment and spite in love. He is sharp, funny, mean, flippant and deadly serious. He shows us that poetry is the thing – perhaps the only thing – that can hold love in words long enough to let us look at it honestly.

Sometime religious outsider and social disaster, sometime celebrity preacher and establishment darling, John Donne was incapable of being just one thing. He reimagined and reinvented himself, over and over: he was a poet, lover, essayist, lawyer, pirate, recusant, preacher, satirist, politician, courtier, chaplain to the King, dean of the finest cathedral in London. It’s traditional to imagine two Donnes – Jack Donne, the youthful rake, and Dr Donne, the older, wiser priest, a split Donne himself imagined in a letter to a friend – but he was infinitely more various and unpredictable than that.

We are, he believed, creatures born transformable. He knew of transformation into misery: “But O, self-traitor, I do bring/ The spider love, which transubstantiates all/ And can convert manna to gall” – but also the transformation achieved by beautiful women: “Us she informed, but transubstantiates you.”

And then there was the transformation of himself: from failure and penury, to recognition within his lifetime as one of the finest minds of his age; one whose work, if allowed under your skin, can offer joy so violent it kicks the metal out of your knees, and sorrow large enough to eat you. Because amid all Donne’s reinventions, there was a constant running through his lifeand work: he remained steadfast in his belief that we, humans, are at once a catastrophe and a miracle.