Another answer to Ken—-
So if I am understanding you correctly, you appear to be saying; If a person is truly saved, he will never break any of the 10 commandments, never slip and make a mistake, and remain perfect for the rest of their lives. And if this person does make such a mistake, then they were never saved in the first place. Is this what you are saying? Or am I misunderstanding you!
No, when someone is saved, they are given the power of God at the moment and for later, to not sin. The sinless state is maintained by the grace of God. “His grace is sufficient, for our strength is made perfect in weakness”. II Cor. 12:9
When someone does sin although they were saved, they go through chastisement and depending on how hard they fell, they may have a difficult time getting back into the place where they are truly walking in the light completely without feeling wounded and/or shamed. However, when they repent completely, they are fogiven and cleansed by the blood of Christ as it says in I John 1:7-9. You must be forgiven. It is possible to lose one’s salvation but not if they just slip in a minor way, only if a deep sin is repeated times without number I’d say but God must be the judge to this. The person doesn’t lose his salvation unless he really knew all the truth and then went ahead and deliberately sinned time after time after time.
Sometimes we can see the person wasn’t really saved in the first place b/c we see that they have no knowledge. They are doing foolish things all the time and making a fool of themselves and bringing destruction on their lives and the lives of their loved ones also.