First, we must address what a worldview actually is. Greg Bahnsen defines it excellently in the book, Pushing the Antithesis:
A worldview is a network of presuppositions which are not tested by natural science and in terms of which all experience is related and interpreted.1
First note that a worldview is a network of beliefs, EVERY worldview. The challenge is to have a network that is consistent within itself and makes sense across the board. If our beliefs do not properly relate to one another, we aren't avoiding the implications of our worldview, we are just being inconsistent. Bahnsen continues:
Unfortunately, many evangelical Christians generally think in a piecemeal fashion, focusing on stray individual doctrines and facts rather than a full-scale, coordinated system of beliefs. They tend to view the Christian faith as a random assortment of free-standing doctrines rather than as a coherent system of interlocking truth claims.2
You see, many people believe that their worldview is like a jar full of marbles. In that jar are placed all of their individual beliefs about things, and they can scoop out beliefs that they don't like, examine them in isolation, and toss them out as they get more evidence.
Instead of marbles in a jar, a worldview is truly a network of beliefs. It is much more helpful to think of a worldview as a spiderweb. At the center we have the ultimate authority of the particular worldview in question, and we have each of the beliefs branching off as natural consequences of the worldview's ultimate authority:
Again, it is quite unfortunate that many Christians hold to many beliefs that are not consistent with their ultimate authority or presupposition. Non-Christians do this constantly because they are created in God's image with a conscience and yet adopt an ultimate authority that is not His word. As such, they often support things that are proper and godly, yet those very things are not consistent with or even diametrically opposed to their stated ultimate authority. As we will discuss in apologetics posts in the future, one of our great goals is to show them their inconsistencies and push them to carry out the logical conclusions of their ultimate authority to the very end.
However, this should not be the case among Christians. Properly developed, ALL beliefs of every Christian should either be explicitly taught in the Bible (their ultimate authority) or derived from it of necessary consequence. Additionally I will add that in theory, Christians should never have disagreements. If all Christians were to think consistently and derive their beliefs on ALL subjects from their ultimate authority, then we would all agree. In practice, we would actually have some minor disagreements about the matters that are of "necessary consequence," but those disagreements would be FAR out on the edges of the web. In actual reality, we see Christians fundamentally differing on a WIDE variety of important issues. It is my assertion that these disagreements result from a failure to think in a proper fashion, ultimately compartmentalizing thoughts and developing differing perspectives on subjects that are actually antithetical from the stated ultimate authority. Bahnsen continues:
You must defend the Christian faith as a package deal. Every particular human experience, thought, or sensation must be seen and understood within the context of a broader system of interpretation of those things. Each part of a worldview must relate to every other part.3
"So therefore, any one of you who does not renounce all that he has cannot be my disciple." Lk 14:33
1 Gary DeMar, ed., Pushing the Antithesis: The Apologetic Methodology of Greg L. Bahnsen (Powder Springs, GA: American Vision, 2007), 42.
2 Ibid, 43.
3 Ibid, 43.