Why does Paul describe grace as reigning in Romans 5:21?
Paul presents grace as reigning to contrast the former reign of sin and old Adam unto death. Reigning implies a king; just as sin held dominion leading to death, grace now reigns through righteousness, providing liberty and freedom unto eternal life by Jesus Christ our Lord.
Les explains that Romans 5:21 uses the picture of a king because reigning implies rule or dominion. Just as sin, or the old Adam, reigned unto death, so grace—this liberty and freedom—is to reign through righteousness unto eternal life by Jesus Christ our Lord. Les then connects this to Romans 6:1–2, where Paul asks whether we should continue in sin so grace may abound, and answers, "God forbid!" The believer is dead to sin and old Adam and should not live any longer therein. Grace brings liberty, but not liberty to go contrary to the Word of God; it is liberty as a believer, and in certain areas behavior must be determined between yourself and the Lord.
That as sin hath reigned unto death, even so might grace reign through righteousness unto eternal life by Jesus Christ our Lord.
How does grace reign through righteousness and lead to eternal life through Jesus Christ?
Grace reigns like a king through righteousness unto eternal life by Jesus Christ our Lord, overwhelming old Adam's rule of sin and death. God does not force anyone; the choice is to let grace rule supreme rather than old Adam. Scripture narrows salvation to Christ alone, for no other name saves.
Why does Paul describe sin as a king in Romans 5:21, and what does grace do in comparison?
Paul describes sin as a king because reigning implies kingship, and sin or old Adam has reigned unto death. By contrast, grace reigns through righteousness unto eternal life by Jesus Christ our Lord. Grace is the liberty and freedom that reigns, not to license sin but unto eternal life.