In Zen Buddhism, a meditative technique exists called the koan. A koan is a question, dialogue, or phrase given by the teacher to the student with the intent of frustrating and "short-circuiting" discursive thought. Because the koan can not be understood rationally, it must recede and allow intuition to apprehend the meaning. Koans are designed so that dualistic and nihilistic interpretations are deliberately incorrect. The solution then is not a verbal response, but a state of mind that is reflected through the student's entire way of being. This shift is evidence of the student's eventual grasping of the true eloquence of the koan.
As in Zen, where a roshi will disseminate koans to the students, a Hindu guru may deliver a mantra to his or her disciple. Through concentration upon the koan or mantra, the student's capacity of perception in regards to a true uninterpreted reality will expand. The guru's role is then finally understood as a doorway. As in Sikhism, the guru is "that which moves you from darkness to light". One drops the need for the "guru" to follow the "Guru". The Guru is beyond dualism and relativism. The Guru is the absolute. It is the One-Statement of reality, the uni-verse.
Again, such a thing can not be comprehended rationally. To philosophically ruminate can be a fun exercise, but does not bring one closer to understanding. To ponder the intricacies of the unmitigated reality to the point of angst is damaging, and this search for answers is fruitless. Eventually cognition is discontented, duality is transcended, nihilism is altogether forgotten, and the questions fall away. The seeker, seeking, and solution are one. All is simply the pearls of Indra's net. The atman is Brahman. I and my Father are one. This is sacrifice. This is surrender. This is grace.