You remove yourself from faith in Christ once you murder, commit adultery, etc., and are unrepentant. If you then die, does God say, "well, he would have repented eventually, so I will hold him close to me in the next life" ?
No.
(Actually, God does know what you would have done, although He does not interfere with free will. That is a Mystery.)
I encourage you to discern between the doctrines of fellowship, salvation, eternal life, eternal security, sanctification.
BTW, the mystery for the Jew was the Mystery Church Age wherein the Holy Spirit indwells the believer. Note that upon salvation, the Holy Spirit indwells us and doesn't depart.
A believer with volition, might indeed decide to turn away from the mind of Christ, perhaps falling back upon some past memories or habits we had in our old sin nature or old man of how we could make order out of chaos (definition of COSMOS or World). In that worldly thinking, we might find a person worthy of being killed and then decide to murder that person. The thought in our soul with volition is also murder. When we add volition to the temptation, then we choose whether to remain in fellowship with Him, or fall out of fellowship and sin. We might turn our mind over to thinking wrongfully, but the Holy Spirit still indwells us.
Christ, when speaking to unbelievers very well communicated to them that murderers, homosexuals, liars, adulterers,etc would not inherit the kingdom of heaven.
It is probably better understood by forst studying each of those doctrines and categorizing them in our thinking in mind and in heart before we slip and confuse fellowship with salvation, or eternal life with the kingdom of heaven.
There are different levels of faith. Our intial faith is what is used by God the Holy Spirit when He regenerates our spirit, when God creates spirit life in the believer.
Any believer who says he never sins after salvation makes God a liar, although through faith in Christ, there is no temptation too great than that which may be resisted.