King Lear

II.ii. When Kent knowingly insults Cornwall and Regan, Cornwall says of Kent “He cannot flatter, he, / An honest mind and plain, he must speak the truth.” Who else does this recall?

I think that that brings to mind Cordelia, since she always speaks her mind.

About Act 2 sns. 2-3:

Kent, in disguise, comes to Regan's castle, and meets with Oswald. Kent starts calling him names, and challenges him to a fight. Cornwall, Gloucester, Edmund and Regan enter, and Cornwall has Kent put in the stocks. Gloucester tries to get Cornwall to let Kent go. Kent gives him the letter from the king. 

Bell