Explain the ‘miracle’ in ‘black ink’ that Shakespeare speaks of in Sonnet 65.

Shakespeare had a deservedly high opinion of his poetic genius. It is a bit uncanny that he seems to be knowing that we will be reading his lines so many years after his death. In quite a few sonnets he claims that his poetry is immortal and in some he assures the person to whom those sonnets are addressed that his poetry's immortality will convey immortality on that individual. This is, of course, a poetic conceit; but Shakespeare's sonnets have been read by millions of people and published in countless volumes in English and translations for some four hundred years and are still popular. Many are so well known that they would exist in people's memories even if every printed copy were somehow destroyed. In that sense they are immortal because they exist independently of the "black ink" in which he wrote them and into which they eventually found their way into print.

In Sonnet 65 the poet tells his paramour that he may be able to perform a miracle of preserving that person's beauty against the ravages of time through the magic of his words, whereas there is nothing else that can hold out against Time. Beauty is frail and time is implacable. One wonderful line in Sonnet 65 is:

Shall Time's best jewel from Time's chest lie hid?

The image is that Time owns a jewel chest into which it places everything that is beautiful just as a woman keeps her jewels in such a chest. The poet's paramour is Time's best jewel, having been produced in the course of time and therefore belonging to Time. 

Shakespeare does not say positively that his Sonnet 65 will perform the miracle of saving his beloved--or at least saving the essence of his beloved's beauty--from Time. The poet does not sound as confident in this sonnet as he does in some other sonnets, such as Sonnet 19 and the marvelous Sonnet 55. In Sonnet 19, which begins with the startling line:

Devouring Time, blunt thou the lion's paws...

he concludes with this very confident couplet:

Yet do thy worst, old Time: despite thy wrong
My love shall in my verse live ever young.

In Sonnet 55, which begins with these famous lines"

Not marble nor the gilded monuments
Of princes shall outlive this powerful rhyme,
But you shall shine more bright in these contents
Than unswept stone, besmeared with sluttish time

the poet concludes with this couplet:

So till the judgment that yourself arise,
You live in this, and dwell in lovers' eyes.

The loved one will remain alive in this sonnet until Judgement Day, and then be resurrected in the flesh as promised in The Book of Common Prayer:

...we therefore commit his body to the ground; earth to earth, ashes to ashes, dust to dust; in sure and certain hope of the Resurrection to eternal life...

The beautiful Sonnet 18 which begins with the famous line:

Shall I compare thee to a summer's day?

concludes with this couplet:

So long as men can breathe or eyes can see,
So long lives this, and this gives life to thee.