Justification and Sanctification

John Piper dotting the i's and crossing the t's on the doctrine of justification:

If Paul had just spent three chapters teaching that justification means God's powerful salvific activity in liberating people from the mastery of sin, why would the question arise: So shall we sin that grace may abound? . . . what gives some measure of plausibility to these rhetorical questions in Romans 6:1 and 6:15 is the doctrine of Romans 3 - 5 that justification is emphatically not liberation from the mastery of sin. It does not include sanctification. That is precisely what creates the need for Paul to write in Romans 6 - 8: to show why God's imputing his own righteousness to us by faith apart from works does not result in lawlessness, but in fact necessarily leads to righteous living. Therefore we are not at all encouraged to blur the relationship between sanctification and justification that Paul preserves in Romans 6:6-7: Justification is the necessary and prior basis of sanctification ("for," v. 7) (John Piper, Counted Righteous in Christ: Should We Abandon the Imputation of Christ's Righteousness?, 77-78).