How we cite our quotes: (Act.Scene.Line). Line numbers correspond to the Riverside edition.
Quote #7
ISABELLA
How would you be
If He which is the top of judgment should
But judge you as you are? O, think on that,
And mercy then will breathe within your lips
Like man new-made. (2.2.99-103)
Here, Isabella echoes Christ's Sermon on the Mount: "Judge not, that ye be not judged. For with that judgment ye judge, ye shall be judged: and with what measure you meet, it shall be measured unto you again" (Matthew 7:1-2). In other words, don't be so quick to judge other people because nobody is perfect and everyone is subject to God's judgment.
When Angelo propositions Isabella two scenes later, we can see just how much this concept applies to the corrupt deputy.
Quote #8
ANGELO
Be you content, fair maid.
It is the law, not I, condemn your brother.
Were he my kinsman, brother, or my son,
It should be thus with him. He must die tomorrow. (2.2.104-107)
When Isabella pleads for Claudio's life, Angelo takes refuge behind the "law" and acts as though he has no choice in the matter when he says that "it is the law, not I" that condemns Claudio.
Still, we know this is a load of bull, because, back in the play's opening scene, Duke Vincentio gave Angelo permission to be flexible when handing down sentences. (See 1.1 above.)
Quote #9
DUKE
'An Angelo for Claudio, death for death.'
Haste still pays haste, and leisure answers leisure;
Like doth quit like, and MEASURE still FOR
MEASURE.—
Then, Angelo, thy fault's thus manifested,
Which, though thou wouldst deny, denies thee
vantage.
We do condemn thee to the very block
Where Claudio stooped to death, and with like
haste.—
Away with him. (5.1.465-475)
When the Duke sentences Angelo to death for what he's done to Claudio and Isabella, he embraces a kind of "eye for an eye" system of justice that suggests Claudio's punishment should be equal to (measure with) the suffering he's caused.