Part two of my response to VirusDoc’s questions in the comments here. I’ll attempt to tackle questions 1 – 3 because they kind of go together:
1) Why do you feel so strongly that Christianity needs *a* definition instead of *many* definitions? Is there evidence within the life or teachings of Christ for such a demand?
Well, I think that there is one small core set of fundamentals that define Christianity and that there can only be one set. If it has many definitions or sets of core teachings, how can it be one? How can several groups or people claim Christ and follow different fundamental beliefs?
That said, I think there are also many means of living beyond that core. Much like a tree grows up from a common trunk and spreads in many directions so does Christianity. Paul spoke of that when he spoke of our many gifts (1 Cor. 12) and different roles (Eph. 4:11-13) but in each passage he speaks of that diversity in the context of unity. It is not an either/or proposition, there must be both. In that same chapter of Ephesians he also speaks of the importance of unity:
Make every effort to keep the unity of the Spirit through the bond of peace. There is one body and one Spirit–just as you were called to one hope when you were called– one Lord, one faith, one baptism; one God and Father of all, who is over all and through all and in all. – Ephesians 4:4-6
Paul’s comparison of the church to the body in 1 Cor. 12 is a great example of diversity from unity. We all recognize a hand or foot as human, a part of the body. However, if a man came to you and had the hand of a baboon or a hoof of a donkey, you’d immediately recognize something was wrong. It was a hand and foot, but not a human hand and foot. I think the same can be said for Christianity. It ought to be recognizable when something is similar but doesn’t belong.
As far as the teachings of Jesus, yes I think there are several:
John 4:16 – No one gets to God except through Jesus.
Matthew 7:13-14 – The narrow road implies a precise definition.
John 17:11, 20-21 – Jesus prays that we may be a united as He and God are. Can you imagine them disagreeing on fundamentals (or anything for that matter)?
Other parts of scripture, some outlined above, teach of the importance of unity. 1 Cor. 1:10 even says that we should ‘be perfectly united in mind and thought.’ Unity is a big deal in the NT.
2) Do you think it is possible that the diversity within Christianity is something God intended?
Absolutely. See 1 Cor. 12 again.
3) In your opinion, where does diversity become disunity (not doctrinally, but practically speaking)?
I’m not sure about that one. I think that this is one of the reasons that defining the core is so important. After all, if everything is fundamental, then nothing truly is. The question then becomes is the disagreement or diversity a violation of any of the core of the faith? If so then I think the line has been crossed.
I think that identifying disunity or divisiveness is something we must approach with caution. It’s far too easy to become the dividing force ourselves by pointing our fingers at others and calling them divisive. Suddenly it is we who are drawing lines in the sand and saying who’s in or out based on our own whims not on scripture. I think that’s why keeping this core value set small and clearly defined is important as well. If we’re to draw lines in the sand, we must do everything we can to draw them only where God would and nowhere else.