Shakespeare wanted to show Macbeth in the early scenes at the height of his glory in order to make the contrast with his depraved and despondent character at the end seem all the more glaringly precipitous. The honors and praise Macbeth receives at the beginning of the play might seem overdone if it were not understood that they were intended by Shakespeare as a prelude to his downfall. All of the praise Macbeth receives early in the play is primarily intended to set him up for his tragic ruin. Shakespeare felt it was necessary to establish what an illustrious person Macbeth was before he committed his terrible murder in order to make his deterioration and death genuinely tragic. Macbeth himself says to his wife:
When something bad happens to a bad man, it is not tragic, but when something bad happens to a good and distinguished man, it is essential to tragedy.
We learn that Macbeth is considered brave and very accomplished as a soldier.
Despite his actions later in the play, what we learn of Macbeth early on is positive. The accounts given of his prowess in battle are overwhelming. He is described as a hero. The bloody sergeant goes before King Duncan and gives an elaborate account of Macbeth’s actions in battle against the traitor Macdonwald, and how he boldly served his country even when hope seemed lost.
He describes him as “brave Macbeth” and says “well he deserves that name” and describes how, dispite all odds when the battle seemed to be against him he plowed through the soldiers with his sword held high. With his “brandish'd steel” he smote his enemy, smoked with bloody execution” he “minion carved out his passage” until he faced his enemy and then cut him straight down the middle (Act 2, Scene 2). The king is clearly impressed.
O valiant cousin! Worthy gentleman! (Act 2, Scene 2)
He is so impressed, in fact, that he immediately demands to know what became of Macbeth, and Banquo, and calls for them. He decides to give Macbeth a promotion right then and there, to Macdonwald’s title, Thane of Cawdor. Currently, Macbeth is only Thane of Glamis and that is a lesser title.
How did Macbeth go from being an honorable soldier to a traitor and a tyrant? The witches certainly intervened, and his wife definitely gave him a shove. However, the characteristics that made him successful on the battlefield—bloodlust, stubbornness, the ability to take a life—certainly did not serve him well in the ordinary world.
For whatever reason, it is important to remember that Shakespeare takes pains to tell us that Macbeth was brave in battle, and a hero. He tells us this to make sure that we know that he fell, and fell tragically. He also opens the play not in the ordinary world, but in the world of the witches. That seems to tell us something too. They might have given him more than a shove in the direction of madness.