Necessity will make us all forsworn
Three thousand times within this three years’ space;
For every man with his affects is born,
Not by might mastered, but by special grace.
If I break faith, this word shall speak for me:
I am forsworn on mere necessity.
(1.1.152–58)

Berowne addresses these lines to the King and his fellow lords, predicting that their oath will fail. He is the only one of the company to question to severity of the restrictions imposed by the oath, and his reservations cause him to hold out on swearing to it. Only at this point does he agree to sign on, in part out of the necessity of the situation. However, he also slyly implies that “necessity” will cause all the lords to break their vow—necessity here referring to the need for food, sleep, and contact with women. In a clear moment of self-awareness, he acknowledges that he won’t be able to survive without these necessities, and he predicts that the same will hold true for his companions. Armed with this awareness, Berowne rests assured that the lords’ “necessity” will excuse them from their inevitable perjury.

Such is the sinplicity of man to hearken after the flesh. (1.1.222–23)

Costard speaks these words in the presence of the King and his lords. The fool has just been arrested by Armado for fooling around in the park with the country maid, Jaquenetta, in violation of the new rules of the court. Before he reads the ridiculous letter of explanation penned by Armado, the King interrogates Costard about his crime. But Costard admits no wrongdoing, and instead he speaks these words that perfectly encapsulate a simple human truth: sexual desire is an undeniable part of life. The word printed here as “sinplicity” appears in the First Folio edition of the play. Though it could be a typographical error, many editors retain it for the spectacular way it undermines the concept of sin by recognizing just how basic and foundational sex is—hence, “sinplicity.” Costard’s words show a clear sense of self-awareness that the lords will struggle to achieve.

Your oath I will not trust, but go with speed
To some forlorn and naked hermitage,
Remote from all the pleasures of the world.
There stay until the twelve celestial signs
Have brought about the annual reckoning.
If this austere insociable life
Change not your offer made in heat of blood;
If frosts and fasts, hard lodging, and thin weeds
Nip not the gaudy blossoms of your love,
But that it bear this trial, and last love;
Then, at the expiration of the year,
Come challenge me, challenge me by these deserts,
And by this virgin palm now kissing thine,
I will be thine.
(5.2.871–84)

After learning of her father’s death, the Princess refuses the King’s plea to marry him before she returns to France. However, she doesn’t reject him outright. Instead, she gives him this ultimatum about retreating for a year to reflect. This is, by extension, the same ultimatum presented by each of the ladies to their respective lords. In making this ultimatum, the Princess points out that she can’t trust the King to know what he really wants, since he’s pursued her “in heat of blood.” Given this uncertainty, and given the fact that his romantic zeal has just caused him to break a much shorter-term vow, she refuses to rush into making “a world-without-end bargain” (5.2.866). She instead directs the King to spend a year in retreat, both to mature and to cultivate self-awareness. Only once he’s truly able to make such a serious commitment will she agree to marry him.