The Big Bang theory supposes that the universe began as an infinitely dense singularity and has since been expanding for billions of years. Though the Big Bang is not communicated in the Genesis account of creation, it lends scientific credibility to the scriptural contention that God created the universe ex nihilo (out of nothing).
First, like the Bible, the Big Bang theory hypothesizes that the universe had a beginning. This claim stands in stark opposition to the scientifically silly suggestion that the universe eternally existed.
Furthermore, if the universe had a beginning, it had to have a cause. Indeed, the cause of all space, time, matter and energy must be nonspatial, nontemporal, immaterial, and unfathomably powerful and personal. As such, the Big Bang flies in the face of the preposterous proposition that the universe sprang into existence out of nothing and lends credence to the Genesis account of a Creator who spoke and the universe leaped into existence.
Finally, though evolutionists hold to the Big Bang, the Big Bang does not imply biological evolution. Big Bang cosmology answers questions about the origin of the space-time continuum, not questions about the origin of biological life on earth.
While we must not stake our faith on Big Bang cosmology, we can be absolutely confident that, as human understanding progresses, creation will continue to point to the One who spoke the universe into existence.
Source (and for further study), see William Lane Craig, On Guard: Defending Your Faith with Reason and Precision (Colorado Springs: David C Cook, 2010).