People often say that Christianity can save you, but actually this isn't true. It has no power to do so, that is, if we speak of it as a set of beliefs and practices. Real Christianity, of course, can save. Let me explain.
You see, in reality, Christianity isn't a philosophy of life you choose to live by. There is some great philosophy within it. It's intellectually robust. It is intellectually and spiritually stimulating. It provides both a coherent sense of the world and a foundation to plant one's feet in chaotic times. But Christianity is first and foremost about Christ. It stands or falls upon the Person of Christ, and that means it stands or falls in your life based upon whether the Person of Christ is truly in your life.
Now, the presence of Christ is in the truth, but not just an intellectual adherence to the truth, but a desire to believe what Christ says because of your love for Christ, not just because you can turn what He says into a cogent philosophy of life. And the presence of Christ is a deeply spiritual experience, but deeply spiritual experiences can be had by those who never meet the true Jesus Christ.
Instead, both revealed truth (i.e., the Scripture) and experience of the truth have their enlivening power only in one's relationship with Christ. It is in His presence, where one has bowed him or herself completely to Him in love, that this relationship with Christ empowers and sets a person's will to believe what is true and to obey what He has commanded.
Hence, as Ravi Zacharias does here, I found the quote he makes of this author to also be very interesting, as the rebellion of the heart almost always pretends to be a rebellion of the head--thus creating the self delusion that one is turning away from truth because it lacks intellectually (as though that assessment was not fully based upon ones presuppositions and ultimate beliefs as a starting point in the first place). http://www.youtube.com/watch?v=76zUvMoy-u8&feature=related
Some leave Christianity because they say it failed them. They say it didn't work. But genuine Christianity cannot be found in how firmly you believe the doctrines, or are committed to the philosophy of its lifestyles, or the reading of its Scripture, or the praying of its prayers, or the singing of its songs, or the external attempt to obey its righteous commands. It is found in a genuine relationship with Christ that is filled with such a love for Christ that one seeks out His doctrines, His lifestyle, His Scripture, His prayers, His songs, and His righteous commands.
It is being "in the vine," and "in Him," as we let Him and His Word dwell/live "in us" (John 15). This is all very intimate relational language in the New Testament. And notice how it is directed to the individual as well as the corporate body ("you" is plural, but "the one who abides in Me" is singular). He has a relationship with us both individually and corporately, and one cannot seek Him in love without seeking out both personal and corporate encounters with Him through His Word (in other words, you can't have a real relationship with Christ by not desiring to encounter Him in the assembly of His people).
My only point is that Christianity fails everyone if a genuine relationship with Christ is not the center of that Christianity. His loving presence is the power and the will to animate what would otherwise be dead. He is the power socket to the electrical gadget of our Christian lives. Unplugged, there is no power that can run it, it dies quickly. Christianity is but a mere corpse with no soul, and like zombies, these people walk around with or without their Christian labels, as dead men.
No, Christianity can't save you. Only Christ can. Christianity is just what comes about if He has. Forget that He powers all of it, and it is simply a matter of time before you reject it--the intellectual excuses coming only as crutch to convince yourself that you didn't reject it because of any deficiency on your part to receive Christ in love, but only on Christianity's part for "not working."
But the true relationship with Christ is filled with grace and truth. It loves Christianity because it loves Christ. It doesn't fight with Christianity because it doesn't fight with Christ. And no one who has such a relationship ever gives it up for some cheaply thought out reasons, because "He who began a good work in you will perfect it until the day of Christ Jesus" (Phil 1:3); and the person in whom Christ dwells in a relationship can boldly say then that "I can do all things through Him who strengthens me" (Phil 4:13).
So if you have Christ, you have everything. If you do not have Christ, you have nothing. Your religion, even if it is Christianity, is worthless to you, and it will fail either now or in the future. But if you have Christ, your life, your Christianity, is as durable as the One in whom it receives its strength, and He lives forevermore.