The disadvantage of being a Catholic in Elizabethan England are difficult to generalize about. On the one hand, as the careers of Donne's father and stepfather suggest, it was possible, if you were sufficiently circumspect or well-connected, to prosper. On the other hand, you might end up having your intestines torn out.
... and also at the heart of his psychology, by describing the mental aftershocks of growing up on such a knife-edge:
Donne's fastidious withdrawal from the great mass of English people is reflected, too, in the style of his poems. Superior, difficult, designed for circulation among a few kindred spirits, they make no concessions to the barbarous clods and half-wits he had the ill luck to be living among.
But the deepest pleasure of Carey's book comes in the way he continually grapples with this most problematic and rewarding of English poets (who's the subject of one of the single most intellectually thrilling essays Open Letters has ever published, which you can read here). Page after page is filled with happy discoveries:
He handles holy things so as to cauterize himself. Elaborate blasphemies are also incorporated into the love poems, as if it were not merely Catholicism but Christianity that Donne had to cure himself of. When he proclaims that his love can be expressed only by negatives, or compares the naked woman in 'Going to Bed' with 'soules unbodied', he is ingeniously perverting what St. Thomas in the Summa Theologica had written about God's nature and the joys of the blessed.
Carey is also excellent in his poem-by-poem defense of the man's genius. Take for example his comments about 'A Hymne to Christ at the Authors last going into Germany' a poem Donne wrote about accompanying Lord Doncaster on an official embassy from James I to the German princes. After noting that some scholars have criticized Donne's veracity (he was travelling in splendor and relative ease, not roughing it in an open boat), Carey is appropriately tart: "... we have only to read the poem," he tells us, "to see that Donne's self-dramatizing urge has produced something so fraught with power that it would be absurd to demand, in its stead, a more realistic estimate of the risks involved." What's going on here is far deeper:
Donne does not so much falsify as master reality, taking one or two fragments as his stage set, and discarding the rest. All the actual circumstances of the embassy are obliterated. The rich coachloads, and the ambassador to whose suite Donne was a relatively minor appendage, vanish without a trace. We are left with Donne looming tragic and solitary above a vessel which seems on the point of disappearing as well. ... The struggle between the ambitious careerist and the lofty scorner of the world's rewards is, in this poem, quite naked.
As in so much of Donne's verse, no matter how clear the ultimate victory in such a struggle might be, there's a pausing, darker note of ambiguity pulling at the strings of its pattern:
In what torne ship soever I embarke,
That ship shall be my embleme of thy Arke;
What sea soever swallow me, that flood
Shall be to mee an embleme of thy blood;
Though thou with clouds of anger do disguise
Thy face; yet through that maske I know those eyes,
Which, though they turn away sometimes,
They never will despise.
Seale then this bill of my Divorce to All
On whom those fainter beames of love did fall;
Marry those loves, which in youth scattered bee
On Fame, Wit, Hopes (false mistresses) to thee.
Churches are best for Prayer, that have least light:
To see God only, I goe out of sight:
And to scape stormy dayes, I chuse
An everlasting light.
Many straightforward biographies of Donne have been written (some more effective than others, as I've had occasion to learn over and over again), but to my mind, the best kind of such work will be something like what Carey does here, an aesthetic study that grounds itself in life-details, rather than a life-study that occasionally indulges in aesthetic digressions. Carey's approach works best in the end because that's the kind of life John Donne chose for himself in the end. It's certainly the only kind of life of himself he'd have been interested in reading - and it'll interest you too, without fail, so find a copy (mine, as you can see, is already spoken for).