The reason that Lady Macbeth is able to convince Macbeth to kill Duncan is because she is able to get inside of his head. She convinces him that he is not a man unless he does the things she suggests. In act 1 scene 7 of Macbeth, Lady Macbeth tells Macbeth tells Macbeth "When you were durst into it, then you were a man;" She is purposefully belittling him so he will do what she tells him in order to feel more like a man. Lady Macbeth, as a strong and steadfast character, is a powerful speaker and uses this towards her advantage when she wants to manipulate Macbeth.When considering the relationship between Macbeth and his wife, at first, one has to ask how is it that the Thane of two strong territories was able to be manipulated by a woman.Since all of Macbeth actions, in the beginning of the play, were controlled and dictated by Lady Macbeth this shows he is insecure and weak. Macbeth is manipulated time and time again. this is not a good characteristic for a king because a king needs to be strong for his people. this shows how Macbeth character was weak.
Lady Macbeth, "pours spirits" into Macbeth. This means she is able to easily persuade him to do things. She finds his weakness, him not being able to give her a child, and uses it against him. She tells him he isn't a man because he cannot give her a baby, but says he can redeem himself by killing Duncan. In act one, Lady Macbeth states "When you durst do it, then you were a man;And, to be more than what you were, you wouldBe so much more the man, (1.7.56-58)" and then goes on to state, "I have given suck, and knowHow tender 'tis to love the babe that milks me:I would, while it was smiling in my face,(1.7.62-64)" saying that he is only a man if he kills Duncan, she then make sure he gets the point by bringing up his weakness of not being able to get her pregnant.
Macbeth becomes emotionally unstable when the thought of killing Duncan comes into his mind. He has a battle with himself mentally for days about whether or not to kill Duncan. If Macbeth did not already have the idea of killing Duncan, it would have been much harder for Lady Macbeth to influence him into doing so. She also knows Macbeth’s greatest insecurity is that he is not able to produce an heir. She says that the only way that he can prove to be a man is to have children, and since he can not do that he needs to kill Duncan. Since Macbeth is very insecure about not having children, he has no choice but to kill Duncan. This suggests that he can be easily influenced.
Lady Macbeth is able to easily influence Macbeth to kill Duncan because of his inherent desire to prove himself. Macbeth always feels the need to prove himself and his worth to others around him. Whether its splitting someone in half on the battle field or just having to be the best noble under the king, his desire to please runs his emotional desires and mental state. This is why when Lady Macbeth suggests for Macbeth to kill Duncan, at first he is hesitant and giving every reason why he shouldn't but as he realizes how Lady Macbeth patronizes him, he can't help but feel the need to prove himself once again. In a way Macbeth strives to please and wants to make sure everyone's expectations of him are exceeded and that there is no doubt that he is a man to anyone, suggesting his ability to be easily influenced to do wrong by those around him.
I believe that Lady Macbeth is easily able to influence Macbeth for three main reasons. All husbands want to whatever it take to make their wife and family happy. Throughout the play Lady Macbeth coaxes Macbeth into doing things she wants done. Also, Lady Macbeth has something that she will always be able to hang over Macbeth's head. The fact that Macbeth is not able to give Lady Macbeth children is always in the back of Macbeth's head, taunting him. Since he is not able to do what the world requires to be a man, he is going to do everything in his power to please Lady Macbeth. Finally, Lady Macbeth's verbal power is so strong. She is constantly able to influence Macbeth and other character in the play to do what she wishes by only using her words.