Why is Macbeth at first unafraid when he finally meets Macduff on the battlefield?

Macbeth, at first, was unafraid when he finally meets Macduff on the battlefield because he thought that Macduff was born of a woman. This means Macduff cannot harm Macbeth.

Explanation:

Macbeth and Macduff are both characters in Shakespeare's tragedy entitled"Macbeth."

Macbeth knew of Macduff's disloyalty to him, thus he diverted his anger towards him. He made a plot to kill Macduff's wife and children while Macduff was in England. Their deaths angered Macduff who vowed to avenge them. He then tracked Macbeth and finally, they faced each other and started fighting.

Since Macbeth could never be harmed by anyone who was born from a woman, he became confident that Macduff will never be able to harm him.

However, Macduff explained that he was taken away prematurely from his mother's womb. So, this means that he wasn't technically born from a woman.

So, this explains the answer.