From an Orthodox Christian perspective, rational arguments for the existence of God, though helpful in explaining to a non-believer that God's existence is rational rather than irrational, come to a dead end by not being able to effectively demonstrate that God exists. Though metaphysics can lead to a certain logical certainty about something, only empiricism can verify and confirm a philosophical or emotional argument. Every argument can present a counter-argument based on logical laws and principles, but empirical scientific observation cannot be philosophically discounted. Therefore, without empirical proof for God and an actual observation, there is ultimately no proof for God's existence to confirm what is inferred through logic.
Orthodox Christianity alone provides the most precise means to empirically prove the existence of God. This scientific method of verifying the divine comes through the process by which man can acquire the Holy Spirit and through glorification (union with God) actually perceive God (Matt. 5:8) in this life, which produces inner faith that is based not on mere acceptance of other peoples observations (the appearances of God to the prophets, apostles and saints), but a faith based on personal empirical proof. In Orthodox theology, one definition of a saint could be that it is someone who has verified the existence of God through empirical observation.