Shakespeare is putting himself down again in this one and he's becoming quite possessive of his lover.

Our story continues with Shakespeare locking John Donne in a trunk.

Sonnet 49

Against that time, if ever that time come,
When I shall see thee frown on my defects,
When as thy love hath cast his utmost sum,
Called to that audit by advis'd respects;
Against that time when thou shalt strangely pass,
And scarcely greet me with that sun, thine eye,
When love, converted from the thing it was,
Shall reasons find of settled gravity;
Against that time do I ensconce me here,
Within the knowledge of mine own desert,
And this my hand, against my self uprear,
To guard the lawful reasons on thy part:
   To leave poor me thou hast the strength of laws,
   Since why to love I can allege no cause.