In short, the relationship between string theory and God can be stated this way: If string theory is true, then God created it. That is the only definitive statement we can deduce from the Bible about string theory. The Bible doesn’t mention whether God used atoms or elements or quarks or eleven dimensions and tiny strings of vibrating energy. All it says is that God made the world (Genesis 1).
Some, however, try to use string theory to learn more about God—not about His character, but His location. God is not confined to the three spatial dimensions and one time dimension that we are (Isaiah 40:22). Heaven does not exist in a space that we can see, and God is outside of time. Some have taken this to mean that if we can’t see God, and if we can’t see most of the dimensions involved in string theory, then maybe God lives on those dimensions. The biggest problem with this theory is that it still places God inside the particular cosmos that was created for mankind. According to the latest version of string theory, all eleven dimensions (time, the three spatial dimensions, and seven others that are too condensed to see) are necessary for the universe as we know it. If that is the case, then all eleven dimensions are things God created, not places where God is confined.
Thinking about God living in eleven dimensions and interacting with the four we have access to is an interesting mental exercise. It might explain why we can’t see Him—an observer living in four dimensions cannot see all of an eleven-dimensional form, although ultimately God cannot be seen because He has chosen to be seen only through the eyes of faith (Hebrews 11:1). If string theory is true, it also might show how He can interact with the world in ways that we can’t describe—and thus call "miracles." And, if God can move freely through all eleven dimensions, it would illustrate how He can be "outside" of time. For Him, leaving the confines of time would be no more difficult than if we were to leave the two-dimensional plane of the street and fall down through a manhole.
Ultimately, we don’t know. Scientists are just beginning to try to explain string theory—a theory that isn’t even testable or observable and, therefore, is not yet even considered legitimate science. If string theory is true, then God created it. If it’s not, it’s at least an interesting metaphor in our attempt to understand God and how He works in creation. “And these are but the outer fringe of his works; how faint the whisper we hear of him! Who then can understand the thunder of his power?" (Job 26:14).