The Sonnets LI - 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 winged 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.'