In act 3, scene 1, Henry appears in a forest, disguised and carrying a prayer book. Thinking that he is alone, he speaks aloud while trying to figure out his next steps in recovering his kingdom, which the Yorks have taken over. First addressing himself as “Harry,” he asks rhetorically how he can help his subjects if he cannot first help himself. Changing his tactic, using the literary device called apostrophe (which includes personification), Henry directly addresses adversity as if it were a person, namely his opponent.

Reversing the situation of opposition, rather than confront an adversary on the battlefield, he treats the enemy as his intimate friend.

Let me embrace thee, sour adversity,
For wise men say it is the wisest course.

His words are at odds with his tone, however. In supplicating this opponent, he is requesting rather than commanding: “let me embrace thee.” This tone indicates his lack of confidence, as does the way he uses variants of “wise”: “wise men say” rather than “I am sure.”

The soliloquy that follows confirms that he is not confident, as he concludes that their rival Warwick, not Queen Margaret, will gain the support they are seeking in France.

King Henry VI says this when he is wondering in the north of England after he has been dethroned and his queen and his son have gone to France to ask for aid. Henry has also long detested the state of civil war into which his land has been plunged. Henry is experiencing great adversity at this moment, as he realizes that no one will "call him Caesar" or regard him as the king. He also realizes that he cannot help others at this moment, as he is not even in a position to help himself. 

This quote means that he must face his difficulties, referring to them as "sour adversity," rather than evade or ignore them, as that is usually the advice given by philosophers and other wise men. The repetition of "wise" and "wisest" in the quote emphasizes that Henry believes he is choosing the right path in facing his troubles. He also refers to "sour adversity" in the second person, as "thee," as though adversity is a familiar friend who he is accustomed to hugging or embracing.

In the opening of the first scene in the third act of Henry VI, the idea of how one can embrace adversity is evident.  The meaning of the quote reflects an approach that one can take towards difficulty.  Adversity is shown to be "sour," and very difficult.  It is filled with some of the most treacherous elements, thorns meant to cause frustration and sometimes pain.  However, Shakespeare suggests that in accepting the condition of adversity and in its" embrace,"  a sense of understanding is evident.  The allusion to "wise men" suggests a knowledge and understanding within the nature of adversity that can prove meaningful to the individual.  

The quote reflects how Shakespeare sees the relationship between knowledge and suffering.  Shakespeare's quote suggests that when individuals embrace or accept the idea of adversity and that which comes with it,one gains understanding.  It is for this reason that "wise men" say it is "the wisest course."  In order for individuals to gain wisdom and a sense of understanding, adversity must be experienced.  Henry VI speaks of this idea when he speaks about the need to accept adversity as part of a course of wisdom.  In order to envision the restoration that he believes is a part of the cosmology of the world, Henry VI speaks of the need to embrace adversity.  His words suggests that doing so enables the individual to gain more insight into the world and one's place in it.