I am still plowing my way through the Bible...about 2 weeks to go. I've been finding the prophets difficult with all the warnings of woes and judgment. (Just finishing up Amos.) It makes me ever more thankful that I am living in this present age of grace. Under the Law, there was the constant need to offer animal sacrifices for sins and trespasses and iniquities.
Interesting to think about the fact, though, that when a sacrifice was brought, the priest did not examine the person who presented it, but rather the lamb, or whatever animal was brought. It always needed to be without blemish. When we present ourselves before God, He is not examining us, but our Sacrifice, the perfect, sinless Lamb of God, without blemish. How completely amazing! How freeing to know that we can come freely to our heavenly Father and He will not turn away from us in disgust and disappointment!
Sometimes the apostle Paul answered accusers who thought he was teaching the idea that, because we are under grace, we are free to live lawlessly, and sin as much as we happen to feel like sinning. For example, Romans 5:1, 2 and 15: "What shall we say then? Shall we continue in sin that grace may abound? Certainly not! How shall we who died to sin live any longer in it?...What then? Shall we sin because we are not under law but under grace? Certainly not!" And Romans 3:8: "And why not say, 'Let us do evil that good may come'? - as we are slanderously reported and as some affirm that we say..."
So why not go ahead and sin, exactly? Paul, in I Corinthians, repeated this thought: "All things are lawful for me, but all things are not helpful (profitable). All things are lawful for me, but I will not be brought under the power of any...all things are lawful for me, but not all things edify" (6:12 and 10:23b). Choosing sin is first unprofitable, secondly addicting, and thirdly not edifying, which is to say, it won't build up but rather tear us down. It's a little like choosing poor diet, sedentary lifestyle and all kinds of unhealthy choices. We're free to do those things, but they only ruin us.
Though we are completely free in the grace of God, we still reap what we sow. That is a law as sure as the law of gravity. Jesus taught this: "Blessed are the merciful for they shall obtain mercy" (Matthew 5:7) and "Judge not that you be not judged. For with what judgment you judge, you will be judged, and with the measure you use, it will be measured back to you...Judge not and you shall not be judged. Condemn not, and you shall not be condemned. Forgive and you will be forgiven. Give and it will be given to you: good measure, pressed down, shaken together, and running over will be put into your bosom. For with the same measure you use, it will be measured back to you" (Matthew 7:1 and Luke 6:37, 38).
Let me just make a clarification here about the "Forgive and you will be forgiven" part. Since Jesus became our propitiation, bearing our punishment and God's wrath against sin for us, we are already forgiven. Ephesians 1:7, 8 says, "In Him, we have redemption through His blood, the forgiveness of sins, according to the riches of His grace which He made to abound toward us in all wisdom and understanding." God's forgiveness is ours. But our own feelings of guilt and condemnation can keep us from fellowshipping freely with our Lord. Also forgiveness from people will come your way more freely if you are one who forgives easily. "Do not be deceived, God is not mocked; for whatever a man sows, that he will also reap" (Galatians 6:7).
So, all that rambling to remind us that we are so, so blessed to have Jesus as our substitutionary sacrifice, giving us the freedom to live in God's marvelous grace and freed from any judgment, but we are foolish to abuse the grace whereby we were justified.