Sonnet 51: Thus can my love excuse the slow offence

Thus can my love excuse the slow offence
Of my dull bearer, when from thee I speed:
From where thou art, why should I haste me thence?
Till I return, of posting is no need.
O, what excuse will my poor beast then find
When swift extremity can seem but slow?
Then should I spur, though mounted on the wind;
In wingèd speed no motion shall I know.
Then can no horse with my desire keep pace;
Therefore desire, of perfect'st love being made,
Shall neigh—no dull flesh—in his fiery race.
But love, for love, thus shall excuse my jade:
    Since from thee going he went wilful-slow,
    Towards thee I'll run, and give him leave to go.