If we deliberately keep on sinning after we have received the knowledge of the truth, no sacrifice for sins is left, but only a fearful expectation of judgment and of raging fire that will consume the enemies of God. Anyone who rejected the law of Moses died without mercy on the testimony of two or three witnesses. How much more severely do you think someone deserves to be punished who has trampled the Son of God underfoot, who has treated as an unholy thing the blood of the covenant that sanctified them, and who has insulted the Spirit of grace? For we know him who said, “It is mine to avenge; I will repay,” and again, “The Lord will judge his people.” It is a dreadful thing to fall into the hands of the living God.
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I know of a men who identified themselves as Christians, and in public, they appeared to be and were highly esteemed by other members of their church. One of them was a leader of the youth group. The other, I'm not sure if he holds a position of authority in the church, but he is very well liked and admired.
The youth group leader was found dead in his car which had been burned to the ground. They had to identify him by dental records. After his death, photos of him were found doing unspeakable things to his step daughter, who was drugged at the time. He apparently committed suicide, likely because of this. Hopefully he did not do this to anyone else in the youth group he led.
The other man abuses his wife and children at home, watches porn at the dinner table, throws a fit and wrecks he and his wife's hotel room after going out by himself after a marriage conference. He renounced Christ, but has those in the church buffaloed into believing that he's a really good, Godly man.
Listening to real life testimonies of demon possession, it stands out to me that often times demons and demon possessed people attend religious gatherings, such as the men described above. Why that is I don't know, other than Satan and his agents hate God, and their purpose is to destroy His people because His people are working to fulfill His plans and purposes. Satan isn't concerned about people who don't believe in God because they are serving him anyway. He is concerned about the people who are serving God, so it makes sense that he and his agents would attend Christian events and gatherings.
One account that I heard about was from a man who was in a worship band at a Christian youth retreat. At one point, one of the other band members came up missing. When they found her later, she was in a daze, staring off into the woods. She said that she saw a dark figure at the edge of the woods beckoning her to come to him. If I remember correctly they took her inside and were eventually able to cast a demon out of her.
Both of the men above seem to have been provoked by demons to do the horrible things they did, but still attended Christian events and gatherings. To my knowledge, both grew up in Christian homes and were Christians for a long time. So what happened to cause them to become this way and to do such terrible things? I don't know their whole story so I can't say, but one thing that comes to mind is that it is possible that neither they nor the households they were raised in were truly Christian. They and their families may have went to church and even served in their church, therefore they and others would identify them as being Christians. But those things in themselves do not make someone a Christian. The word Christian in the Bible was first used in Antioch to describe Jesus's disciples who love and obey Him. So a Christian is someone who loves and obeys Jesus. Unfortunately not everyone who goes to church or who serves in their church loves and obeys Jesus. There are weeds mixed among the wheat in our churches. The abusive man was himself abused by his parents. Do real Christians abuse their children? Though there may not be any specific teachings of Jesus against abuse, it certainly does not align with God's character or any kind of behavior that He would advocate for or allow of His people. People who do not follow the teachings of Jesus or who behave contrary to His ways and teachings cannot be said to be Christians even if they go to church and call themselves such.
Some people who once were Christians, simply fall away and no longer follow Him. Like a dog who returns to its vomit, they revert back to their sins, and to the world and its wicked ways. Jesus tells of a house where demons resided and were cast out and the house was cleaned and spotless. But then the demons were permitted to return, and the house became worse than it was when they previously occupied it. In the same way, some Christians who fall away from God become worse than they were before.
A lot of Christians would say that people who come to Christ and then fall away were not really Christians to begin with because God will not let us go once we believe in Jesus. Not only does that idea go against free will - that God allows us to make our own choices and decisions - but also against Scripture, such as Hebrews 6, where it says that it is possible for "those who have been enlightened, who have tasted the heavenly gift, who have shared in the Holy Spirit, who have tasted in the goodness of the word of God and the powers of the coming age", to fall away (Hebrews 6:4-6). The things described in that passage seem to be describing someone who knew God and was inhabited by the Holy Spirit - a Christian.
Jesus cautioned His disciples often of falling away, and we even see where many of His disciples left Him because His teachings were too hard for them (John 6:60). He told a parable of how some will fall away due to the devil coming and taking the word from their heart after they hear it, so that they will not believe and be saved; due to having no root after receiving the word with joy after they hear it, so they believe for a while but fall away during the time of testing; due to being choked by life's worries, riches, and pleasures, so they do not mature (Luke 8).
After sharing with his disciples that they are going to be hated by the world, he said to them, "All this I have told you so that you do not fall away." Then He goes on to tell them that their own people are going to persecute them and try to kill them. He warned them so that they would not be surprised by it when it happened, because the shock of it may cause them to fall away.
Paul also described a "falling away" occurring when the man of lawlessness appears before Jesus returns (2 Thessalonians 2:3). This will occur because their faith will not be rooted in truth, therefore they will not be able to persevere when tribulations and persecution comes.
If only Christians were taught this in church today, rather than that they are safe because God is going to protect them and remove them from tribulations, there may not be such a massive falling away when they are tested by tribulations, and when the man of lawlessness appears before Jesus returns. However, it is predicted in the Bible to happen, therefore it will. In fact, it will likely get worse rather than better as time draws closer to the return of Christ. There will be more people who hear about Jesus and repent and believe, but many who currently believe will fall away due to the reasons Jesus cited.
People who make the decision to leave God after experiencing Him, do so by being enticed by sin. They give into the temptation of sin, which unless they repent, will eventually harden their heart, and lead them to death by no longer wanting to follow Jesus. "Death" being both spiritual and physical death. A Christian has life in Christ; we are spiritually alive, born again. But sin causes both spiritual and physical death. A Christian cannot live in both sin and obedience to Jesus. If he lives in sin, he will eventually die spiritually and his spiritual death will in turn lead to his physical death because he will no longer have the eternal life that believers in Jesus obtain. When someone dies spiritually, they no longer have an interest in God or the things relating to Him. They no longer love Him or want to serve Him. And according to John, our assurance of knowing God and being in Christ comes from keeping Jesus's commandments, His word. Whoever says that they abide in Him, will walk as He walked. If someone says they know Him but do not keep His commandments, they are a liar and the truth is not in them (1 John 2:1-6).
Jesus, James, John and Paul warned the church of the dangers of falling away because it is very important that we remain in Christ and persevere when trials, tribulations, and persecution comes. Jesus warned to remain in Him or be cut off and thrown into the fire.
I know people it has happened to. I have seen people who were Holy Spirit filled brothers or sisters in Christ walk away from Him and leave everything behind for sin and the world. I myself have experienced the struggle of leaving Jesus and returning to my former sins and the world's ways. There are times when the temptation is very strong, so I have to remember how good and delightful God and His word are, and that my sins nor the world are worth leaving my Lord and God for.
The men I described at the beginning may have had this happen to them. I don't know if it did or not. We cannot know what goes on in a man's heart or mind, or judge if he is truly saved or not. It seems apparent though that neither of these men were followers of Jesus, at least at the time they committed such heinous acts. Maybe they never were, or maybe they once were but fell away, or maybe they somehow became possessed by demons. Who knows for sure.
Some may wonder why demon possession would even be a consideration. Maybe they were just bad people, or they suffered from a mental disorder. Maybe so, but the Bible speaks of casting out demons, especially when Jesus was here, because He was given all authority over all powers, principalities, and authorities, in order to destroy the works of the devil. He did not contribute their symptoms to a mental health disorder, but to demons, and He cast them out of people who were tormented by them. I'm not saying that mental health disorders do not exist, because I believe they do, or that everyone who does bad things is demon possessed, but at least some people who commit heinous acts of evil do so because they are provoked by demons. Many things that we contribute to mental health disorders today, could possibly be related to demonic activity.
I think this is likely the case of these two men. What other reason is there for a man to find it acceptable to beat his Christian wife and kids, and then deceive others into believing that he is a really good, Godly man? What other reason is there for a man to threaten the life of his Christian wife and make it his life's purpose to destroy her because she left him to protect her children and herself from his abuse, and then deceive others into believing that she is the abuser and that the kids are unsafe with her? What other reason is there for a man to watch porn at the dinner table while his wife and kids are sitting there next to him? He renounced Jesus and "reversed" his baptism. He is displaying antichrist behavior and exhibiting the attributes of Satan - lying, deceiving, killing, stealing, and destroying. Satan was a liar from the beginning and he came to steal, kill, and destroy, just as he has pledged to do to his wife.
How about the guy who raped his step daughter on several occasions, and who knows who else, and then killed himself because he could no longer stand the thought of doing such terrible things? Did he do these things on his own, or is it possible that demons provoked him to do them, and the only way he knew to end their torment, and his, was to commit suicide? We don't know, but we do know that the devil’s purpose is to kill and destroy the people of God.
Hebrews calls a person who has received the knowledge of truth, but deliberately keeps on sinning, an enemy of God. Anyone who is an enemy of God, perhaps like these men who have done terrible and wicked things, should be fearful because they can expect judgment and to be consumed by raging fire. They once knew God and were sanctified by God and were considered to be among His people, but they turned away from Him and commited evil, trampling the Son of God underfoot, treating the blood of Christ's covenant that sanctified them as an unholy thing, and for insulting the Holy Spirit. They will die and be punished severely without God's mercy because it is God who said, “It is mine to avenge; I will repay,” and again, “The Lord will judge His people.” It is a dreadful thing to fall into the hands of the living God, therefore it is something that Christians should consider when tempted to leave Jesus for sin and the world.
Remember those earlier days after you had received the light, when you endured in a great conflict full of suffering. Sometimes you were publicly exposed to insult and persecution; at other times you stood side by side with those who were so treated. You suffered along with those in prison and joyfully accepted the confiscation of your property, because you knew that you yourselves had better and lasting possessions. So do not throw away your confidence; it will be richly rewarded. You need to persevere so that when you have done the will of God, you will receive what he has promised. For, “In just a little while, he who is coming will come and will not delay.” And, “But my righteous one will live by faith. And I take no pleasure in the one who shrinks back.” But we do not belong to those who shrink back and are destroyed, but to those who have faith and are saved. Now faith is confidence in what we hope for and assurance about what we do not see. - Hebrews 10:26-11:1