Favourite Othello quote.

Act 3 Scene 3.
(Iago to Othello)
"O, beware, my lord, of jealousy!
It is the green-eyed monster which doth mock
The meat it feeds on."

This is my favourite quote in the play as not only does it show Iago's awareness of the emotion that he can use to toy with in Othello, but it also enables us to see his status as we realise that he is the one to unleash this "monster" in the end.
We can see the personification of jealousy as a "green-eyed monster", and I think that this represents the sheer power of this emotion that begins to eat Othello up in Act 3 Scene 3. Jealousy is a key theme in the play, as it is one of the key reasons behind Othello's downfall at the end.