Sonnet 22

My glass shall not persuade me I am old,So long as youth and thou are of one date;But when in thee time's furrows I behold,Then look I death my days should expiate.For all that beauty that doth cover theeIs but the seemly raiment of my heart,Which in thy breast doth live, as thine in me:How can I then be elder than thou art?O, therefore, love, be of thyself so waryAs I, not for myself, but for thee will;Bearing thy heart, which I will keep so charyAs tender nurse her babe from faring ill. Presume not on thy heart when mine is slain; Thou gavest me thine, not to give back again.
I've decided, on further reflection, to declare my undying affection: even as we get old,I'll have and I'll holdyou heart, and not (just) your erection.