Isabella’s sound reprimand of her brother when he dared to ask her to consent to what was essentially her rape(3.1) seemed, at the time, wholly justifiable to me.  Whether she was afraid of her own basic, human desires more than the act itself was not a major concern, simply because it was her decision, a very personal and possibly emotionally scarring decision.  In the same position, many women would be torn and miserable if asked to make such a decision no matter what course of action they may choose.

However, this view changed when I was confronted by her rather abrupt change if heart in falling to her knees to beg for the salvation of Angelo (5.1). The strong overtones of Christian imagery make this an enlightened and beautiful act of growth and true justice, but it calls to my mind questions of her true reasons for her anger at Claudio. Her love of her brother was not strong enough to allow her to even entertain the thought of being bedded for his salvation, but the man who in essence attempted to rape her and murder Claudio is deemed forgivable? Her brother who simply begged to be saved, called on her ‘love’ to save him she condemned to bitter, restless death but Angelo was worthy of her falling to her knees for his life? This draws into question yet again the idea of degrees of sin. Are some sins more forgivable than others? Is Lucio more sinful than Claudio? Is Mariana less sinful than Juliet?

Rereading the scene in the prison between Claudio and Isabel, I have decided that the “lady doth protest too much”  (Hamlet 3.2).  No longer does she appear as the chaste, inexperienced woman balking at an insult against her Christianity and purity and instead has transformed into a woman terrified of her own desires, of the possibility of enjoying that which she has been taught to view as sinful.

(I rather like the differences between these two interpretations of the Act 3 Scene 1.)
http://www.youtube.com/watch?v=XUaCwSASd24
http://www.youtube.com/watch?v=L7siwW5Oqnk