There are several “versions” of Christianity floating around lately. If the following is not included, then it’s not Christianity. This is a biblical, thumbnail view of the necessary beliefs that one must have if we are to be called Christian:
We are all sinners who have sinned, rebelled against a Holy God by violating his holy law.
God in his grace has provided means by which we can be made right with God and be saved.
God became flesh in the person of Jesus and died on the cross as our substitute. He pays the price and penalty pronounced against us by God’s judgment against us. He rose on the third day so that we too may rise with him.
We receive salvation when we confess our sin, repent (turning away from our sin), and trust in Jesus (place our faith in him) as our Savior and Lord.
Jesus is the Lord of our lives. He owns us and rules us. We are then enabled to live the Christian life by the influence of the Holy Spirit. The Holy Spirit, the third person of the Trinity, is given to every believer as a seal of and guarantee of our salvation so that we may obey him and his commands.
Christ will return one day to gather his people and take them home. Until that day, God’s people gather together as the church, the Body of Christ where we worship, encourage one another, and practice living in heaven until Jesus returns.
Certainly there are other major doctrines, but these are core beliefs. Without them Christianity would fade into paganism.