Evangelical Christians buy T-shirts and bumper stickers that proclaim this slogan:

Christianity is not a religion; it is a relationship with Jesus Christ.

http://www.christianapparelshop.com/p-526-christianity-is-not-a-religion-christian-t-shirt.aspx?

The problem with this slogan is that a relationship is NOT the sort of thing that can be true (or false):

1. If Christianity is a relationship, then Christianity is true only if a relationship is the sort of thing that can be true (or false).

2. A relationship is NOT the sort of thing that can be true (or false).

Therefore:

3. If Christianity is a relationship, then it is NOT the case that Christianity is true.

But the Evangelical Christians who buy T-shirts and bumper stickers proclaiming that “Christianity is a relationship” are ALSO going around proclaiming that “Christianity is true”.  These claims are logically incompatible.  If one accepts the view that “Christianity is a relationship”, then one must also REJECT the view that “Christianity is true”.  Thus, the T-shirt and bumper sticker buyers are (surprise, surprise) asserting logically contradictory claims.

The Christian apologist James Sire is more sophisticated than these T-shirt and bumper sticker buying Evangelical morons, but he, nevertheless, falls into a very similar self contradiction.  Sire asserts that the Christian worldview is true, but then he defines “a worldview” in a way that makes this impossible:

A worldview is a commitment…  (Naming the Elephant, p.122)

The same sort of objection applies to Sire’s proposed definition of “a worldview”:

1A.  If the Christian world view is a commitment, then the Christian worldview is true only if a commitment is the sort of thing that can be true (or false).

2A. A commitment is NOT the sort of thing that can be true (or false).

Therefore:

3A.  If the Christian worldview is a commitment, then it is NOT the case that the Christian worldview is true.

But Sire, like virtually all Christian apologists, asserts that “Christianity is true.” and that “The Christian worldview is true.” Thus, just like the morons who buy the T-shirts and bumper stickers, Sire contradicts himself by asserting that the Christian worldview “is a commitment”.

Religious experience is another thing that some Christians would like to identify with Christianity or the Christian worldview, but this is just another example of the sort of category mistake made by moronic T-shirt buyers and by James Sire:

1B.  If Christianity is an experience, then Christianity is true only if an experience is the sort of thing that can be true (or false).

2B.  An experience is NOT the sort of thing that can be true (or false).

Therefore:

3B. If Christianity is an experience, then it is NOT the case that Christianity is true.

If someone wants to claim that “Christianity is an experience”, then he/she will have to give up the widely held belief (among Christians) that “Christianity is true”.

People are free to define “Christianity” or “the Christian worldview” however they wish, but people are not free to define “Christianity” and “the Christian worldview” in a way that contradicts some other statement that they wish to proclaim to the world.  So, if Christians want to stop proclaiming that “Christianity is true”, then I have no problem with them re-defining “Christianity” to mean whatever they want it to mean.

However, if they decide to use the word “Christianity” to refer to a feeling, an experience, a commitment, or a relationship, I will then respond: I couldn’t care less about your feelings, experiences, commitments, and relationships; I’m interested in truth and knowledge, so please go away and don’t bother me with insignificant blather about your feelings, experiences, commitments, or relationships.  Don’t talk to me unless you have some (alleged) bit of truth or knowledge to share with me.

Wear the stupid T-shirt if you wish, but don’t wear the stupid T-shirt and then try to convince me that “Christianity is true”; just wear the T-shirt and shut your ignorant pie hole.