Definitely, Neoplatonism was a big influence on Abrahamic philosophical thought. Though the real locus classicus for God is Aristotle's Metaphysics, specifically his description of the unmoved mover. There are some not-so-minor differences between Aristotle's theology and Abrahamic theology, but God insofar as he is the ground of all being is a concept that most clearly originated in Aristotle's work.