Modal Ontological Argument
(1) If an eternal being exists, then there is no potential for this being to not exist.
(1a) An eternal being is, by definition, without end. Any being which has the potential to stop existing is not eternal.
(2) If an eternal being does not exist, then there is no potential for this being to exist.
(2a) An eternal being is, by definition, without beginning.
(3) An eternal being either exists or does not exist.
(3a) This disjunction is exclusive, both disjuncts cannot both be true.
(4) That which has no potential to exist is logically impossible, or has a nature which violates the law of non-contradiction.
(5) The nature of an eternal being does not violate the law of non-contradiction.
(5a) Thus, it is not the case that there is no potential for this being to exist.
(5b) If it is not the case that there is no potential for this being to exist, then it must be the case that there is no potential for this being to not exist.
(6) Therefore, an eternal being exists.
(7) An eternal being cannot be made of anything.
(7a) Formless matter is impossible; any matter will always have some form, even if that form is chaos.
(7b) If an eternal being is made of matter, then the being would have came into existence once the matter attained its form (since the form is what this being is) which would require either the being to give form to its own matter or be shaped by some other being.
(7c) Both options in (7b) would contradict the idea of eternity.
We can thus conclude from logic alone that an eternal immaterial being must exist. This does not prove the God of the Bible, but it opens the door to the numinous. This plants the seeds for the acceptance of special revelation, especially given the consistency of the Abrahamic God as being eternal and immaterial, as opposed to being an anthropomorphic super-being.