It is often claimed by skeptics that you either have “faith” or “rational” reasons for what you believe in. However, this presents us with a false dichotomy. Someone can have both faith and rational reasons for why they believe something to be true. At the fundamental level, everyone has faith to the degree that eventually, one needs to appeal to a reliable authority in areas of admitted ignorance. However, faith in a reliable source is not at all irrational. Not only can one have both faith and rational reasons for what they believe to be true, but one could also have rational reasons for placing their faith in a reliable source.
For Christians, faith is rational and reasonable. However, we do not claim that faith is something we have in and of ourselves. We recognize that “faith” itself is a gift of God (Ephesians 2:8, Philippians 1:29). We do not have the kind of faith that saves us by an exertion of our intellectual prowess; rather, while our faith is indeed eminently rational, it is given to us by God’s grace through faith. Our believing and trusting (biblical faith) in Christ is a miracle of God; however, once we affirm faith in God and His revelation through His Word, we are gifted with an outlook on life (in the Bible) that confirms the reality that our faith is rational. Indeed, only when we place our trust in Christ and believe the totality of His Word will we truly have a genuinely rational outlook on the world. Indeed it is the biblical outlook on the world that provides a foundation for rationality Itself, much less the specific rational reasons we provide for the particular things we believe in.
On the biblical account, man is created in the image of God (Genesis 1:26); and as such, man thinks, applies logic and rationality just as God does but to a lesser degree. On the biblical account, God has created an orderly world in which man can make predictions and engage in science. On the biblical account God has given His Law to man so as to provide an objective standard by which to live our lives. The biblical outlook provides the foundation for all areas of life such that a logically coherent and well founded intellectual framework gives us the proper lens through which live and understand this world. Faith and rationality are not at odds; rather it is eminently rational to place one’s faith in Him who provides a foundation for rationality itself.