When my son was younger he believed in the Lord Jesus Christ. Since coming back from war, seeing what he saw and doing what he had to do, he now says that all religions are the same. Controlling and killing each other, all man made. I know that once we are sealed, nothing can separate us from God. But can a person ask the Lord to forgive him, believe in Him, and then turn away from him?
The Lord Jesus often compared us to sheep and called Himself the Good Shepherd. Sheep are not responsible for keeping themselves from wandering off and getting lost. That’s the shepherd’s job. Our Good Shepherd said no one can take us out of His hands (John 10:28-29) and that He’ll never lose even one of us (John 6:39).
Some people would have you believe the phrase “no one” means “no one but ourselves”, indicating that we can relinquish our salvation. But that puts words in the Lord’s mouth. It violates the clear intent of the shepherd/sheep analogy, and renders His promise meaningless.
Besides, the Bible says, “It is God who makes us stand firm in Christ. He anointed us, set His seal of ownership on us, and put His spirit in our hearts as a deposit, guaranteeing what is to come (2 Cor. 1:21-22). When we become believers we are not our own any longer. We’ve been bought at a price (1 Cor. 6:19-20) which is the precious blood of Jesus (1 Peter 1:18) and God, who owns us, has taken responsibility for keeping us.
People can wander away because of personal experiences like your son has endured, but it’s the Lord’s job to bring them back, and He’s promised us a 100% recovery rate.