5:19. For as by the disobedience of one man, many were made sinners: so also by the obedience of one, many shall be made just.
5:20. Now the law entered in that sin might abound. And where sin abounded, grace did more abound.
That sin might abound. . .Not as if the law were given on purpose for sin to abound: but that it so happened through man's perversity, taking occasion of sinning more, from the prohibition of sin.
5:21. That as sin hath reigned to death: so also grace might reign by justice unto life everlasting, through Jesus Christ our Lord.
Romans Chapter 6
The Christian must die to sin and live to God.
6:1. What shall we say, then? Shall we continue in sin, that grace may abound?
6:2. God forbid! For we that are dead to sin, how shall we live any longer therein?
6:3. Know you not that all we who are baptized in Christ Jesus are baptized in his death?
6:4. For we are buried together with him by baptism into death: that, as Christ is risen from the dead by the glory of the Father, so we also may walk in newness of life.