Will the Believer lose their salvation? Will the Believer continue to receive Grace? Does the Believer walk away from God? What happens?
If they leave the truth that Jesus is Lord and Savior there is no coming back.
Some people believe it is not possible but the Bible warns us of it.
Heb 6:1 Therefore leaving the principles of the doctrine of Christ, let us go on unto perfection; not laying again the foundation of repentance from dead works, and of faith toward God,
Heb 6:2 Of the doctrine of baptisms, and of laying on of hands, and of resurrection of the dead, and of eternal judgment.
After we are saved we leave the essentials and move on to be like Christ led of the Spirit.
Heb 6:4 For it is impossible for those who were once enlightened, and have tasted of the heavenly gift, and were made partakers of the Holy Ghost,
Heb 6:5 And have tasted the good word of God, and the powers of the world to come,
Heb 6:6 If they shall fall away, to renew them again unto repentance; seeing they crucify to themselves the Son of God afresh, and put him to an open shame.
If a person leaves the truth that Jesus is Lord and Savior for an alternate reality of another belief of Jesus, or another religion, or an atheist, and they mean it there is no coming back to the truth for they went back to the world and became a part of it, and God will not allow them to go through the process of being saved again by repenting.
Which this is an example.
1Ti 4:1 Now the Spirit speaketh expressly, that in the latter times some shall depart from the faith, giving heed to seducing spirits, and doctrines of devils;
1Ti 4:2 Speaking lies in hypocrisy; having their conscience seared with a hot iron;
1Ti 4:3 Forbidding to marry, and commanding to abstain from meats, which God hath created to be received with thanksgiving of them which believe and know the truth.
1Ti 4:4 For every creature of God is good, and nothing to be refused, if it be received with thanksgiving:
1Ti 4:5 For it is sanctified by the word of God and prayer.
Some will depart from the faith, so they had faith and confessed Jesus as Lord and Savior, but they forsook the truth and believed the Bible according to the occult, and evolution, and believed Jesus is not Lord and Savior, but a good teacher and evolved to be an ascended master and avatar, so if they believe that they made a mistake and believe again that Jesus is Lord and Savior they cannot be saved again.
They will forbid to marry for population reduction, and command to abstain from meats, nature worship, reverence of animals, because they hold a wrong viewpoint of the Bible.
But if a person believes this but has not accepted Jesus as Lord and Savior then they can turn to the truth that Jesus is Lord and Savior and be saved.
Some people do not believe once you have faith that you can lose it, but the Bible warns us of it, and some will depart this faith and follow the new age movement interpretation of the Bible in which they believe in evolution, and people are still evolving but this time to be spiritual provided by the New Age Christ in the future.
These people cannot come back to the truth if they leave the truth that Jesus is Lord and Savior, but a person that went to the new age movement and has never confessed Jesus as Lord and Savior can come to the truth and be saved for they never left it.
God will not allow a person to be saved again if they leave the truth of Jesus as Lord and Savior for an alternate reality whether the occult, or another religion, or another interpretation of Jesus, or being an atheist.
If someone has doubts concerning the truth after they accepted it does not qualify for they have not determined wholly in their heart concerning it, but in their doubt there is no salvation and must get rid of it, but in doubt there is hope, but in departing and mean it there is no hope.
The time will come when the world will only want to hear the Bible according to the new age movement in which they hold the interpretation of Jesus as not Lord and Savior, but a good teacher and love, and evolved to be spiritually great as they want to be too, which will be the unified religious system, and will cause the world to rebel against God and then it is the end.
Some will depart from the faith and follow them.