John Wesley on Romans 5:20

The law came in between - The offence and the free gift. That the offence might abound - That is, the consequence (not the design) of the law's coming in was, not the taking away of sin, but the increase of it. Yet where sin abounded, grace did much more abound - Not only in the remission of that sin which Adam brought on us, but of all our own; not only in remission of sins, but infusion of holiness; not only in deliverance from death, but admission to everlasting life, a far more noble and excellent life than that which we lost by Adam's fall.