Should the Christian faith be rationally defended?
No and Yes.
No, because one man's rational thoughts, arguments, conclusions etc. are not always anothers. Rationality is many times in the eye of the beholder.
For instance with regard to the existence of God, rationally, I can conclude:
That life as we know it demonstrates intelligent design. There are those in the scientific community who, while not being Christians or even theists, have themselves come to that same rational conclusion.
That if life on earth demonstrates intelligent design, ergo there must be a designer. Various persons in the sciences have also come to that rational conclusion.
That if life on earth has an intelligent designer this one must have had a reason to build this intelligently designed world. Intelligent life does nothing of purpose without a reason, even play has a reason.
That if this intelligent designer had a reason to make this world then that reason should, to other intelligent life, be apparent by its design. Just as the reason for a toaster or an airplane or a typewriter would be apparent to other intelligent life.
That the reason behind this design is more than simply the making of life because this world is much more than abundant life. Within the framework of this world lies the knowledge of (and the ability to explore and grasp onto that knowledge) all the known material sciences, of the humanities, of the beauty and the horror, of the greatest and lowest of the beasts and mankind, of the greatest love and most destructive hate and so much more.
That there is only one intelligent life-form on this planet who has demonstrated its ability to understand all of the above and to put that understanding to constructive or destructive use. As a consequence all other life, intelligent or not, are subject to this superior life-form by virtue of their inability to disassemble or distill what has been contructed here and thereby learn from it.
That this superior life-form is here by special design by virtue of the fact that it is the only one who has the capacity to intelligently learn and benefit from the various constructed physical systems and natural laws, the virtual laboratory of sciences as well as by the very real agonies and ecstasies that exist here in abundance.
That because of the unique place this superior life-form occupies over all other living things, even having the potential to purposely destroy itself and all life on earth; the reason for the existence of this superior life-form must be one different than that of other life forms on this planet.
That the possibility this planet's existence may be solely and directly the result of and for that superior life-form should be considered.
That, if that is the case, then this superior life-form may either mean more to its intelligent designer than all the other life-forms or was made for a singularly significant purpose, one highly valued by its intelligent designer. (personally I believe the latter.)
That, that purpose is apparent to some and will one day be apparent to all.
Now, that's my rational thinking but I am quite sure not a few here dismissed it from the very beginning as being the rantings of an irrational mind.
Rational defenses are in the minds eye, who hasn't spent time trying to understand the rational defenses and discussions of politicians, of the Iraqi war, of kids and prisons, of intuition (the eye of the subconcious mind) verses logical deduction (the eye of the conscious mind) and a host of other things? What's rational to one is not always considered rational to another. You can gather together the most prestigious group of scientists in any field or the most respected of religionists in any religion and find among them those who think one or more of their colleagues' thinking processes is irrational.
Defending Christianity rationally and successfully only works with like minds and hearts. Like minds and hearts though are many times found in the most improbable of places, so in the end....
Yes, it is reasonable to attempt to defend Christianity rationally.
Sabrina