It seems to many people that mathematics is the study of pure abstractions. Numbers and perfect triangles float out in a realm of pure thought. Yes, mathematics can be done in the head, without pen or paper. But in practice there is interaction among three realms: (1) persons, who do the thinking; (2) rules, which govern the thinking; and (3) a world out there in which mathematics has applications.
These three things--persons, rules, and a world--all come from God. God is the actual source of mathematics. God is one God in three persons. He is a God of unity. And that unity is the foundation for the unity of any subject, including mathematics. It is the foundation for the stability of any concept, like the concept of a number.
God is three persons. God is a God who has diversity within himself, infinitely and forever. That diversity is the foundation for the number system, beginning with the counting numbers. Two is distinction from one. God is also the infinite God who fills all things. His presence is the foundation for our experience and thinking about space, which leads to geometry.
So mathematics is dependent on God. And it looks different when we realize where it comes from.
Vern Poythress, Ph.D. is distinguished professor of New Testament, Biblical Interpretation, and Systematic Theology at Westminster Theological Seminary.
For Professor Poythress' full treatment of this question:
Vern S. Poythress, Redeeming Mathematics: A God-Centered Approach (Wheaton, IL: Crossway, 2015).