"He isn’t even a being. He is the source of all being"
"To exist in eternity is to exist outside of time, to not be limited by time"
You see, for God to create the universe, he must be outside of it. That means he is outside of our three spatial dimensions, as well as our fourth dimension, time.Sources
1. St. Thomas Aquinas, Summa Theologiae I, Q4, Art 2, https://www.newadvent.org/summa/1004.htm
2. Peter J. Kreeft and Ronald K. Tacelli, Handbook of Catholic Apologetics (San Francisco: Ignatius Press, 2009), 98.
3. Ibid
4. Frank J. Sheed, Theology for Beginners (Cincinnati: Servant Books, 1981), 19.
5. Matt Fradd, "Who Created God?" Catholic Answers, February 20, 2013, https://www.catholic.com/magazine/online-edition/who-created-god