Sonnet 109 is the first of two truly remarkable sonnets that speak of William Shakespeare's own infidelities towards his young lover during a period of prolonged absence.

Although they do not form a strictly tied pair, together these two poems position our poet and his relationship in an entirely new light, because they for the first time genuinely acknowledge that he, too, like his young lover, has succumbed to temptation elsewhere while they were apart, but they both affirm him to be the only one who ever mattered and the one who truly matters now.

With Sonnet 108, William Shakespeare loops back into sentiments expressed intermittently since Sonnet 76, but particularly again recently in Sonnet 105: I have essentially said it all, there is nothing I can do other than repeat and reiterate and rephrase the praises I have sung and continue to sing for you. What it also picks up from Sonnet 105 is the religious tone this set with a there still fairly oblique reference to the Holy Trinity. This was already amplified, though subtly, in Sonnet 106, and here finds a whole new level of what may potentially be perceived as impudence, if looked on from a devoutly religious perspective.
What it also does – and this may in some respects for our observation be most directly relevant – is to tell his young lover yet again that he is showing signs of age, but that to him, Shakespeare, this doesn't matter.

Of all the poems in the collection first published in 1609, Sonnet 107 most clearly and most compellingly seems to refer to external events that shape Shakespeare's world.

Because of this, it takes up a pivotal position in the canon, since it may therein hold clues to both its date of composition and to the person it is addressed to. And while there is little doubt in most people's mind that its references are indeed intentional and allude to some momentous occasion that has passed off signally better than anyone at the time would have predicted, and that in the ensuing calm and peace our poet feels that his love and his poetry have been given a new lease of life, no-one can tell with absolute certainty just what Shakespeare is actually referring to or whom he is talking to, or even whether the two factors are directly or only indirectly linked, or not at all.

There are, however, significant clues, and so much of our discussion of this sonnet will concern itself with what these are and what they mean for our reading of this and the other sonnets in the series.