King Duncan stands as a symbol of stability, and as an idyllic representation of the possibility of just leadership. Boasting admirable traits indicative of a benevolent ruler, it is in fact Duncan’s level-headed, kindly nature that all but sets him up for an untimely demise. As a bastion of peace and order, his character offers a contrast to the other major players as they engage in varying degrees of threats and sabotage in an effort to seek his titleship.
In folk or fairy tales, long-standing peaceful traditions are often represented by an old or dying king. In the case of Duncan, his moral compass serves as a contrast to those who not only wish to see him usurped, but desire to have a direct hand in doing so, and his death signifies the end of that peace as well as the onset of a corrupt regime. Duncan’s decency and trust in both Cawdor and Macbeth not only pave the way for a more dramatically ironic betrayal, but also speak to the precariousness of power in a world where power corrupts. Even if the king is a just and fair one, he is all the more at risk of having his life and legacy destroyed at the hands of those craving power.
Lastly, as the representation of that which is stable and all that came before, Duncan stands as a seemingly immovable force to which all of his surroundings react. The existence of the structure that Duncan provides essentially forces the status quo to either remain as it is, or be destroyed entirely. The prophecies uttered by the three witches foreshadow these changing tides, culminating in his death at the hands of Macbeth.