Rambam describes the concept of "overflow" which explains how an incorporeal God gives life and sustains the entire universe. Of course this is only how we as human beings can describe something we are incapable of actually conceiving.

Guide For the Perplexed - Lecture 62: Part 2 Chapter 13

Join us as we study the monumental work of Maimonides, The Guide of the Perplexed. Let Maimonides speak to us in a language that we can understand, about issues that continue to perplex us in the 21st century. Learn how to approach those difficult times when what we believe seems to conflict with what the Holy writings say.