(Weeping Woman, Pablo Picasso)
Is it for fear to wet a widow’s eye
That thou consum’st thyself in single life?
Ah, if thou issueless shalt hap to die,
The world will wail thee like a makeless wife;
The world will be thy widow and still weep
That thou no form of thee hast left behind,
When every private widow well may keep,
By children’s eyes, her husband’s shape in mind.
Look what an unthrift in the world doth spend
Shifts but his place, for still the world enjoys it;
But beauty’s waste hath in the world an end,
And, kept unused, the user so destroys it.
No love toward others in that bosom sits
That on himself such murd’rous shame commits.
This poem continues the theme of the previous sonnets; namely, an encouragement to marry and have children. The return to the theme is here taken my means to two related metaphors. First, Shakespeare raises a potential objection: If you will not marry because you do not want to leave a widow who will weep at your death, you are wrong. Even if you do not leave a particular woman as your widow, you will leave the world as a widow. Moreover, even if you leave a widow, when you leave a child behind you leave a consolation for the widow. But if you die without children, you leave no solace to others.
Therefore, your objection does not really flow from a love of others. Instead, this waste of beauty, beauty which does not reproduce is really selfishness rather than selflessness.
 Is it for fear to wet a widow’s eye
 That thou consum’st thyself in single life?
 Ah, if thou issueless shalt hap to die,
 The world will wail thee like a makeless wife;
Is it really because you are afraid to leave a widow, that you are refusing to marry and have children? No.
Wet a widow: a useful example of alliteration: the repetition of the w’s draws the two words together in a single concept.
Raising the issue of selfishness, notice “thou consum’st thyself in single life”. You are devouring yourself by being single.
Issueless: without issue, without a child.
Hap: happenstance, luck.
Makeless: without a mate, spouse. And so, the world itself will weep just like a woman who has lost her husband (thus is makeless).
If you die without a wife, you still be mourned.
 The world will be thy widow and still weep
 That thou no form of thee hast left behind,
 When every private widow well may keep,
 By children’s eyes, her husband’s shape in mind.
The first line ends with a double accent: STILL WEEP. This double accent slows down the reading and creates an emphasis: weeping is unavoidable.
The sorrow will be that you have not left your “form” behind in a child.
Thus, the world will be worse off than an actual widow. A “private widow” will at least have a child in whom she can see her husband’s form. And by seeing the child, can keep her husband in mind. But you having left nothing make that impossible for all.
 Look what an unthrift in the world doth spend
 Shifts but his place, for still the world enjoys it;
 But beauty’s waste hath in the world an end,
 And, kept unused, the user so destroys it.
An “unthrift” would be one who misuses money. To be thrifty is to take care with money.
SHIFTS but his PLACE: If a fool wastes all his money, it does not hurt the broader world, “for still the world enjoys it.” The world gets use of the money. The fool is the only one affected. He “shifts his place” in the world.
It is different if you destroy beauty. While the money remains in the world, beauty consumed disappears. If the user does not beget children, he “destroys” the beauty.
 No love toward others in that bosom sits
 That on himself such murd’rous shame commits
The couplet returns to the ostensible objection raised in the first line. You claim that it is really “love” toward a potential widow that keeps you from marrying. I will not marry, because I don’t want to break a woman’s heart by dying. But that is not how the world works. You really do not love others by refusing to marry. You are simply murdering your own self, your beauty, your family that never is or will be; all in the name of trying to spare them.