There are several factors involved:
(1) The Basic Human Factor: the Bible is the revelation of an infinite God, but man is not only very finite, but sinful and very prone to error. This is true even for the believer who is indwelt with the Holy Spirit, the Spirit of Truth and our teacher. We would like to think that with the Spirit indwelling us, we would all come to the same conclusions, but since none of us are perfectly objective (without preconceived notions), nor mature (always room for growth), nor always listening to His leading as we should, Christians often come up with different perspectives on the same passage of Scripture. Part of this is due to the different backgrounds and pre-understandings from which we approach our Bible study. While the Bible is an objective body of truth, as finite beings we are always subjective in our study even though we may seek to be objective and seek to allow the Word to be our authority. Further, in spite of themselves, people typically allow their egos get in the way and they tend to protect their theological turf or the doctrinal positions they are comfortable with. So, we have to constantly examine our hearts and seek to block out our preconceived notions in order to allow the Scripture with its context, historical background, meaning of words, grammar, the analogy of Scripture as a whole, and the type of literature (literary genre) of the passage (history, poetry, epistle, prophetic, narrative, etc.), to become our authority and then be willing to put aside our prejudices and say, “I was wrong” or “I need to reexamine my position on this.
Closely related here is the “hidden agenda” factor. Often, well meaning preachers or pastors take their personal agendas into a passage or look for a passage they can use because of its wording to promote some goal they want to accomplish. But in the process, they butcher the passage and rather than teach what the passage says, they use it to promote their own goal. For instance, I heard a pastor use Philippians 3 to teach the fact we must all learn to accept change and move on. We must put aside our old traditions and be willing to accept new ideas. The staff was evidently having trouble getting people to accept changes they were seeking to bring about in the church, so a passage was found that spoke of forgetting the things behind and moving on to new things. But that is not the primary point of that passage.
(2) The Personality or Fan Club Factor: Here is another element that plays an important role in the many different views. People too often become star struck with some dynamic personality and teacher and follow them into whatever position they take. Rather than being Berean like (Acts 17:11) in listening to the teaching of the Word, there is a tendency to blindly follow their favorite teacher. If their favorite teacher takes a position, because they have so much trust in the man (his charisma, his intellect, his training, the school he is from, looks, etc.), that’s the position they accept. Both Paul and the Lord Jesus warned their disciples about this kind of nonsense. In Mark 4:24f the Lord warned against listening to the wrong message and messengers (like the Pharisees) because doing so would have eternal repercussions. If one rejected Jesus as Messiah, that would mean the loss of eternal life. If a believer followed the wrong messenger, that could lead to the loss of rewards. Then in Luke 8:18, he warned about how a person hears. One can be apathetic, ego driven, and so on. We need to watch our hearts and allow the Word to be our authority, not men. See also Paul’s warnings in 1 Cor. 3:1-4:7; 2 Cor. 11:1f.
(3) The Satanic or Demonic Factor: The cold hard truth is that Satan, the deceiver and liar, walks about seeking to lead people astray. He has his ministers who masquerade as ministers of light who teach demonic doctrines. They may even look like sheep, but in truth they are wolves in sheep’s clothing (cf. 1 Tim. 4:1-3; 2 Cor. 11:1-15; Matt. 7:15). So the New Testament (see Matt. 7:15; 2 Pet. 2:1f; and 1 John 4:1f) warns us to be on alert, to not believe just anything, but to test the message and the messengers? Does the message line up with Scripture? Do the messengers truly demonstrate Christ-like character?
This means we need to work at being careful students who use sound Bible study methods (2 Tim. 2:15-16) and who, like those at Berea (Acts 17:10-11), search the Scriptures to allow God’s Word and the Spirit to lead us into the truth.