Sonnet III:

That glass, one face doth from another, shield,
When mirrored, grace thy fair and barren bloom.
To form another, thou wouldst not be healed;
So blest, wouldst thou thy mother’s youth resume?

No fairer she, shouldst thou thy youth regain;
Nor he, by his posterity revealed.
Thou must not still thy husbandry disdain;
But fury-chafe, an till thy blighted field.

Doth Winter’s harvest care to April’s thresh;
Or dare to rite the golden Spring again?
Cares now Thy Prime for Legacy as Flesh;
When thou art loved and fond in love remain?

So choose: Thy tomb, in single fray enmesh;
Or Heaven’s womb, thine image pray make fresh.

This sonnet is part of a short, or
possibly at some point, very long
sequence; click here to read it all:

Sonnet III: (William Shakespeare)

Look in thy glass, and tell the face thou viewest
Now is the time that face should form another;
Whose fresh repair if now thou not renewest,
Thou dost beguile the world, unbless some mother.

For where is she so fair whose unear’d womb
Disdains the tillage of thy husbandry?
Or who is he so fond will be the tomb
Of his self-love, to stop posterity?

Thou art thy mother’s glass, and she in thee
Calls back the lovely April of her prime:
So thou through windows of thine age shall see
Despite of wrinkles this thy golden time.

But if thou live, remember’d not to be,
Die single, and thine image dies with thee.