In Macbeth, how does the sergeant characterize Macbeth in Act I? What images does he associate with Macbeth?

From the sergeant's description of Macbeth in battle, we can conclude that Macbeth is a strong and valiant soldier who does not retreat, despite the odds against him. Macbeth fights furiously in defense of his King and country, his sword smoking with "bloody execution." Fighting his way through the forces arrayed against him, Macbeth finds the traitor Macdonwald  and "unseamed him from the nave to th' chops, ' And fixed his head upon our battlements." Macbeth does not hesitate in battle; he is relentless in his destruction of the enemy. When Macdonwald is defeated, Macbeth's position, along with Banquo's, is then overwhelmed by a new assault of Norway's army. Rather than retreat, Macbeth fights even more furiously, winning the battle.

In his recounting of Macbeth in battle, the sergeant compares Macbeth (and Banquo) to an eagle in relation to a sparrow and to a lion in relation to a hare. Furthermore, he says Macbeth and Banquo were "[A]s cannons overcharged with double cracks [explosives]."