Many substances give a temporary feeling of euphoria/well-being while harming the cells and systems of our bodies. Some of them don’t alter our state of consciousness (refined sugar, salt, tobacco products), some of them do (alcohol, amphetamines, narcotics). Sin is the transcendent version of those things — it often makes us feel good for a little while, but always leads to death.
Sin is simultaneously opposed to law (I Jn 3) and uses law to kill us (Rom 6-8). This is a very confusing dynamic at first, but it all comes down to the heart. Paul says that a heart set on God is going to sin, but not because it wants to. It’s because sin uses our weakness compared to the standard of God’s law to trip us up. John says that we’ll always have sin, and that not all sins lead to eternal death. What John and Paul both agree on is this — we are totally powerless by ourselves, but God’s grace covers our mistakes.
Sin is also a relentless, enslaving force. Few passages more clearly demonstrate this than Romans 6-8. This discourse seems almost contradictory at several points, but I believe this is by design. There is a constant tension between gratitude for grace and recognition of our own sinful nature. I believe this is stated the way it is to keep us in the proper mindset. On the one hand, we have God’s grace and that covers our sins. On the other, we don’t want to run too far with it and fall from grace. This section details a struggle within each Christian to serve God only, while our bodies furiously pull us towards sinful actions and thoughts. Paul’s conclusion at the end is two-fold: Wretched man that I am, who will deliver me from this body that only brings me death and There is no condemnation for those who are in Christ Jesus.
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