I love St. Paul's Epistle to the Romans. It's right there in your face, isn't it? I love directness, even when it hurts.
"Consequently, brothers and sisters,
we are not debtors to the flesh,
to live according to the flesh.
For if you live according to the flesh, you will die,
but if by the Spirit you put to death the deeds of the body,
you will live." Romans 8:12-13