Because the Scriptures are permeated with warnings and examples of apostasy, it is most amazing there is any false teaching on the subject. In the sixth chapter of Romans alone, Paul asks four simple questions in verses 1-3 and three more questions in verses 15-16. Each series of questions clearly demonstrates it is possible for a Christian to live in sin and be eternally lost.
Having already considered the first quartet of questions, consider this triplet: “What then? Shall we sin because we are not under law but under grace? Certainly not! Do you not know that to whom you present yourselves slaves to obey, you are that one’s slaves whom you obey, whether of sin leading to death, or of obedience leading to righteousness” (Romans 6:15-16).
Thinking that being freed from the tyranny of sin and God’s certain condemnation of sin in the Law of Moses means I can indulge in ungodliness and fleshly lusts because I live under the reign of grace is as wrongheaded as you can get. Such thinking cannot be any wrong-er. Justification by grace is designed to makes me free to be a voluntary, obedient slave of righteousness.
Because I am a slave of the one to whom I present myself in obedience, I am either a slave of rebellion and sin or a slave of obedience and righteousness. Autonomy from these two possible kinds of slavery does not exist; these are the only two options you have in life.
Justification from the guilt of past sins is of no value if I refuse to live a life of sanctification in the present. Walking in darkness eliminates the possibility of walking with God, because He is light and in Him there is no darkness (1 John 1:5).
Any more questions?
