Although Shakespeare conveys a great deal more information about Macbeth through his dialogue and asides (those moments when he speaks aloud to himself, but no other characters can hear what he says), the only moment when he is truly "described" by someone else is when Ross and Angus approach him to say that Duncan has given him the title of Thane of Cawdor.  

Ross says that the king has heard and rejoiced at all the news of Macbeth's success in battle, all of his brave services to the kingdom. He says, "As thick as tale / Came post with post, and every one did bear / Thy praises in his kingdom's great defense, / And poured them down before him" (1.3.101-104). In other words, reports just kept pouring in, one after another, to the king, and each one sang Macbeth's praises for his immense courage (and success) in defending Scotland from rebels and from Norway.