Macbeth Act 1: Scene 6 and 7

Scene 6:

Duncan and his attendants arrive at Inverness and are captivated by its beauty, peaceful ambience and by the grace with which their hostess, Lady Macbeth, greets and looks after them.

Macbeth does not come to meet them at this time so that no one reads his thoughts on his 'open face'. He waits for his wife to return with the news of the king's arrival and rest.

Macbeth goes through a moment of hesitation. Sudden ambiguity takes hold and he launches into the famous 'dagger' soliloquy. He realizes that Duncan is at his castle and has a claim over Macbeth's protection in two ways. Macbeth is both a relative of Duncan as well as his subject. 

Stronger than both these reasons was the fact that Duncan was his guest and as a host, he was sworn by honour to protect his guest. As a host he should be shutting the door against any murderers rather than committing the deed himself. Besides, Duncan has been a gentle and kind king who shall be praised even after his death and his murderer condemned. Each eye would look at him with animosity if he were to be found guilty of the charge. Every eye will shed a tear for the king and curse the murderer. Eventually, he decides that he shall not proceed with the plan to kill Duncan. He had been recently honoured by the king and everyone had a golden opinion about him. He did not wish to tarnish these yet.

When Lady Macbeth hears of Macbeth backing off from the plan, she mocks and challenges him. She tells him he would only be seen as a 'man' if he truly did perform the deed. She tells him that they must go ahead as this was the opportune moment and success was nearly guaranteed. The guards have been drugged and the king sleeps peacefully, oblivious to his fate.

Macbeth is so moved by Lady Macbeth's passionate declaration and challenge, that he tells her to only give birth to sons because only males would be worthy of her grit and determination. They discuss that once the king has been murdered, it would be easy to place the blame on the drugged guards if he used their weapons/knives to kill the king.

Convinced of the success of the plan, Macbeth proceeds to the king's chamber. He says that the false expressions on his face must hide the wicked thoughts of his false heart.