A fornicator is an unmarried person who has sexual intercourse with a person he/she is not legally married to. An Adulterer is a married person who has sexual intercourse with a person who is not his/her legal wife/husband.
Sexual Union is a sacred union that must exist only within the confines of the marriage institution. When people who are not married to each other engage in sexual relationship, it is a sin before God and will not go unpunished.
The bible says in Hebrews 13:4- Marriage is honourable in all, and the bed undefiled:
but whoremongers and adulterers God will judge. In 1 Corinthians 3:18-17, Apostle Paul wrote the following: Know ye not that ye are the temple of God, and that the Spirit of God dwelleth in you? If any man defile the temple of God, him shall God destroy; for the temple of God is holy which temple ye are.
Sexual immorality includes fornication, adultery, homosexuality, lesbianism, bestiality, masturbation, indulging in pornography, and all acts that are sexual in nature that do not edify you body which  is the temple of the living God. Every other sin; done outside the body, but the sin of sexual immorality is a sin against your own body which is the dwelling place of God’s Spirit. See I Corinthians 6:18-20- Flee fornication. Every sin that a man doeth is without the body; but he that committeth fornication sinneth against his own body. What? know ye not that your body is the temple of the Holy Ghost which is in you. which ye have of God, and ye are not your own? For ye are bought with a price: therefore glorify God in your body; and in your spirit, which are God’s.
Some people lust with their eyes. When you look lustfully at a person that you are not married to and you begin to fantasize about having Sex with that person, then you are committing adultery/fornication in your mind. See Matthew 5:27-28- Ye have heard that it was said by them of old time, Thou shall not commit adultery: But say unto you, That whosoever looketh on a woman to lust after her bath committed adultery with her already in his heart.
For most other sins, the bible admonished us to resist, and contend to overcome, but when it comes to sexual immorality, we are admonished to flee.. flee, as used in 2Timothy2:22, is from the Greek word “pheudo” which means, amongst other things, to vanish There is no superman when it comes to sexual immorality, so the best path of escape is to avoid every situation that will put you at a vulnerable position.
Sexual Immorality looks pleasurable on the surface but it is a way that leads to death. Continuing in the practice of sexual immorality will eventually bring about a tragedy. By it many great men have been rubbished and brought down. If you do not get a hold of your body and discipline yourself to the extent that you are able to flee at the appearance of sexual sin, then you are headed for hell fire.
There are Christians who are currently suffering under the bondage of lust. They do not like it and want to come out of it but they keep falling into it. A lady sent me a text message in which she told me that she was under the yoke of masturbation. She was always consumed with guilt and a feeling of dirtiness after indulging in it, yet she would always go back to it. She wanted to come out of that yoke; that was the reason she sent me the text message.
Like this lady, a lot of believers have been held in the prison of pornography, masturbation, fornication, adultery and homosexuality. They do not like it and want to come out of it but it has become a bad habit that they cannot easily shake off their shoulders. If you are currently under the hold of sexual immorality, I assure you that as long as you are willing to get delivered, the word of God that is coming your way right now has capacity to deliver you from the bondage of lust and help you begin to live in righteousness.
Sexual Immorality is not something any responsible person should be proud of. Even outside the fold of Christianity, it is considered irresponsible behaviour for a person to indulge in sexual immorality. Apart from stealing your time and money, reducing your feeling of self worth and reducing your effectiveness, sexual Immorality does a Lot of harm to your Christian walk. It steals your boldness in the presence of God and makes you doubt your place as a genuine child of God. You can’t be talking about effective prayers or wish to increase spiritually and yet perpetuate in fornication, adultery, watching pornographic films, lusting after the opposite sex, etc. Spiritual growth is monitored and established by the Holy Spirit but the Holy Spirit will not remain in a body that continues in sin.
If you are someone who is indulging in iniquity, you cannot have an effective prayer life. Your prayer life will be void. See John 9:31 – Now we know that God heareth not sinners: but if any man be a worshipper of God, and doeth his wilt, he will heareth.
The above is why there is so much unanswered prayer in Churches all over the world. There are churches ever but sin and unrighteousness has hindered prayers from being answered. God always has capacity to hear and answer when His children call upon Him, but sin brings a separation between God and man. See Isaiah 59:1-2- Behold, the LORDS hand is not shortened, that it cannot save; neither his ear heavy that it cannot that ear: But your iniquities have separated between you and your God, and your sins have hid his face from you, that he will not hear.
James 5:16b says- The effectual fervent prayer of a righteous man availeth much. Only the prayer of a righteous man is effectual and availeth much- has power to change any situation.
The issue of prayer not being answered has nothing to do with the devil; he does not have the capacity to stop your prayer from being answered. This is because when you are praying, you are not talking to the devil, you are talking to God and the devil cannot be around when you and God are talking. Your relationship with God is a spirit to Spirit relationship; there is no third party. Only sin can prevent your expected answer.
Immorality is a very serious sin. Do not meditate on it. Do not give yourself to it. Do not relate with anything that will lure you into it. When you sense it, run for your life. It can destroy your life. They which do such things shall not inherit the kingdom of God. That is the tragedy of the fornicators and adulterers. You will not make heaven. You can’t perpetuate in these sins and expect to make heaven.
See Galatians 5:19-21- Now the works of the flesh am manifest, which are these; Adultery, fornication, uncleanness, lasciviousness, Idolatry,  witchcraft, hatred, variance, emulations, wrath, strife, seditions, heresies, Envying, murders, drunkenness, revellings, and such like: of the which I tell you before, as I have also told you in time past, that they which do such things shall not inherit the kingdom of God.
Also see I Corinthians 6:9-10- Know ye not that the unrighteous shall not inherit the kingdom of God? Be not deceived: neither fornicators, nor idolaters, nor adulterers, nor effeminate, nor abusers of themselves with mankind, Nor thieves, nor covetous, nor drunkards, nor revilers nor extortioners, shall inherit the kingdom of God.
Beloved, where are you headed for’? Where is your destination when you leave this world? If you continue in sexual immorality, your destination is hellfire. Only genuine repentance and strong determination to keep your body in check will place you on the path that leads to eternal life.