Do you remember that historic phrase, "Huston, we have a problem."? Well, Christianity has a problem, too, and it's as deadly as the one faced by Apollo 13. The problem I'm speaking of is the many false doctrines and theologies that have infiltrated Christianity so deeply that those who practice them are no longer Christians. Some of these doctrines and theologies render some professing "Christians" completely non-Christian – Literally, Christian cults. That's why everyone should use the Bible Alone for Doctrine and Theology.
Bible Alone for Doctrine and Theology
"Trust in the LORD with all thine heart; and lean not unto thine own understanding. In all thy ways acknowledge him, and he shall direct thy paths." (Proverbs 3:5-6)
So, we should trust the LORD (Yahweh) and not ourselves or other people for our doctrine and theology. Trusting His Holy Bible – the Word of God is the only way to stay on His path for our lives.
Christian – Follower of Jesus Christ who is obedient to the entire moral law of God described in the Bible and worships Jesus as the eternal, self-existent God.
Jesus – Jesus Christ, as described in the Bible, is the second person of the thrice Holy Trinity. He is the almighty God who became a person who was fully God and fully man simultaneously. Jesus is the Son of God and God the Son who created the heavens and the earth and everything within them. Jesus is the self-existent God that exists now, before the creation of His Universe, and always. John 1:1-3, John 8:58, John 20:28, Colossians 2:9, Hebrews 1:8
This Jesus is the Jesus genuine Christians follow. If you don't worship the Christ described by the Bible, you worship a false Christ.
Bible – God's complete revelation of His will for humanity. A collection of divinely inspired books, psalms, proverbs, and letters written by God through men who were specially selected by God. It is God's inspired, breathed, inerrant, infallible Holy Word. No additions or subtractions are permitted to the canon of scripture. Canon is from the Greek word kanon, meaning "standard." The canon of scripture is the "gold standard" and the only authoritative Word of God.
These definitions are at the core of what Christians must believe, but there are other core doctrines. But I will not go into them today. Today, I want to focus on what people try to add to the fixed canon of scripture.
Other Religious Writings
The following are to be rejected by Christians – The religious books and documents of all non-Christian religions, including Islam, Hinduism, Buddhism, Taoism, Shinto, Witchcraft, Vudu, and pagan religions. They would include all religious writings and books from professed "Christian" religions, including Mormonism, Jehovah's Witness, Catholicism, or any other writings held in the same regard as the Protestant Bible. No religious writing or book is equal to or superior to the authority of the Bible.
I'm sure you have noticed that Christian beliefs are not very inclusive. Point of fact – they are completely exclusive. Christianity will not interfere with your religious practices but will also not accept or integrate them into Christianity. Christians will try to convince you that Christianity is the only true path to heaven and eternal life. But we will never try to force it upon you because Christianity is a relationship with God, not a spiritual catharsis.
Strange Non-Christian Beliefs
Some strange beliefs and practices have crept into "Christianity" that are bazar, sinful, and unbiblical.
Being slain in the spirit (fainting, falling, or convulsing because of being overwhelmed by the Spirit of God)
Being drunk in the spirit (appearing drunk because of being overwhelmed by the Spirit of God)
Speaking in tongues in an unbiblical or disruptive manner. Acts:2
Failure to acknowledge the triune nature of God. Matthew 28:19
Christians are "little gods" (Christianity is not polytheistic with a chief god and lesser gods, like Hinduism), so the "little gods" theology is blasphemy
The health, wealth, and prosperity heresy (God did not remove the thorn in the flesh from Paul after multiple prayers) 2 Corinthians 12:7, Matthew 5:10-12, John 15:20. Prosperity preachers would call on Romans 8:32, but, in context, that verse is talking about spiritual things, not tangible things. Every verse that they use to justify this heresy is similarly taken out of context. 2 Corinthians 9:6-7, Philippians 4:19. In 3 John 2, he says, "Beloved, I wish above all things that thou mayest prosper and be in health, even as thy soul prospereth." This verse is a simple greeting to the letter's readers and not a doctrinal promise of health, wealth, and prosperity to all Christians.
The "God is sovereign over heaven, but God needs permission from us to act in our lives" heresy. This heresy is one of the most egregious heresies because God is completely sovereign over everything that ever has or will exist. God's will is supreme, and we must accept His will without regard to our own will.
You should hold a preacher, pastor, evangelist, or expositor of God's Word in higher regard than others. This practice is improper because we are all considered equal in the sight of God. People deserve respect without regard to their vocation or spiritual maturity.
The Sozo prayer technique is akin to the kundalini prayers of Hinduism that put you in an altered state of consciousness and open you up to suggestions. It's almost like hypnotism.
The rhythmic, repetitive modern "Christian" music puts you in an altered state of consciousness and opens you up to suggestions. Again, it's almost like hypnotism.
The "some sins are no longer considered sins because love trumps sin" heresy. In other words, people think that loving others for who they believe they are without regard to what the Bible says is the loving attitude Jesus would agree with. But Jesus is God and never changes, so if a person acts on anything God ever considered a sin, it is still a sin today and forever. Homosexuality – sin; cross-dressing – sin; sex without being married – sin; sex with someone other than your spouse – sin; sex with animals - sin.
Universalism is the belief that everyone will be saved and go to heaven.
Modalism is the belief that the Father, Son, and Holy Spirit are three different modes of God, as opposed to a Trinitarian view of three distinct persons within the Godhead.
Arianism is the belief that Jesus Christ is not fully divine but is a created being.
Modernism is the belief that all doctrines are subject to change and that doctrines ought to change depending on the time and location. In other words, there is no absolute truth or morality.
New Age Christianity is a collection of beliefs and practices from various ancient and modern sources that emphasize personal transformation, spirituality, and alternative approaches to health. It also looks forward to a new era of love and light brought about by humanity, not Christ.
Christian Tarot card reading, or "Destiney Cards," is an unbiblical practice of paganism used by Bethel Church in Redding, California, and others. Galatians 5:19-21
Christian psychic readings and séances are another heresy forbidden by Biblical scripture. Bethel Church in Redding, California, also practices this heresy. Deuteronomy 18:10-12
Bible Alone for Doctrine and Theology
There is an almost exhaustive number of unbiblical writings, doctrines, theologies, poly-theologies, and pagan practices out there, and none of them has anything to do with Christianity.
To genuinely practice Christianity, you must use the Bible as your only authoritative reference. We are not to worship the Bible because that would be idolatry. We are to obey God according to His will, as revealed through the Bible. I submit that you don't know God's will unless you have read, studied, and understood the Bible.
Sola scriptura is Latin for "by Scripture alone," it's one of the key slogans of the Protestant Reformation and genuine Christianity.
The Muslims call us the "people of the book," and that book is the Bible. Christians should always endeavor to be "people of the book." We should obey its moral laws and glean wisdom from the Bible's life lessons, parables, psalms, and proverbs. The Bible is the Word of God and our only authoritative reference for Christian worship, Christian morality, Christian living, and our Christian worldview. Use the Bible Alone for Doctrine and Theology.
References  Bible Gateway passage: Proverbs 3:5-6 - King James Version. (n.d.). Bible Gateway. https://www.biblegateway.com/passage/?search=Proverbs+3%3A5-6&version=KJV  Bible Gateway passage: 3 John 2 - King James Version. (n.d.). Bible Gateway. https://www.biblegateway.com/passage/?search=3+John+2&version=KJV