The cause of all things is the will of God

"The will of God is so the cause of all things, as to be itself without cause, for nothing can be the cause of that which is the cause of everything. So that the Divine will is the ne plus ultra of all our inquiries; when we ascend to that, we can go no farther. Hence we find every matter resolved ultimately into the mere sovereign pleasure of God, as the spring and occasion of whatsoever is done in heaven and earth." - Jerome Zanchius, Absolute Predestination, pg. 16 - 17