These lines are spoken by a captain who has been wounded in the war. He is relaying the information about Macbeth's brave fight against the enemy to King Duncan. He talks about how brave and valiant Macbeth was, so the audience can infer that he is a fierce warrior who will stop at nothing to ensure his win in a battle.
One (internal) is from your thoughts or the characters thoughts and the other one (external) is from what is actually happening to or around the character.
