Romans 11:33–36 is a masterful presentation of the doctrine of God that affirms such things as His wisdom, knowledge, inscrutable judgments, and more. Because the doctrine of God is foundational to all of our theology, we are going to take a short break from our study of the book of Romans to look at various aspects of theology proper, or the doctrine of God. Volume 2 of Dr. R.C. Sproul’s teaching series Foundations will guide our study.
We begin with a brief look at the Lord’s existence. Both the natural world and Scripture testify that our Creator exists (Ps. 19; Rom. 1:18–32), but what kind of being is He? We learn from the Word of God that our Creator is a Trinity.
“One in essence, three in person” is the most concise definition of the doctrine of the Trinity. The Christian faith is not polytheistic, confessing many individual gods, each with its own peculiar divine nature. The Christian faith is not unitarian, confessing that the one divine nature is possessed only by a single person or a single acting subject. Instead, the Christian faith says that three distinct persons are the one divine nature in its entirety. The Father possesses all that makes God who He is; the Son possesses all that makes God who He is; and the Spirit possesses all that makes God who He is. We do not worship three gods, each of whom has his own power, his own intelligence, and so on. Instead, we worship three persons who hold in common the same power, the same intelligence, and so on.
Many biblical passages teach the Trinitarian existence of God. Among the most famous of these is John 1:1–18, which says that the Word—the Son—is both identical to the Father in some way and distinct from Him in another. Another important passage, Matthew 28:18–20, commands us to baptize people in the name of the Father, Son, and Holy Spirit. Such a text shows us that within God Himself there is both a unity between Father, Son, and Holy Spirit (one name) and a distinction (three subjects or persons).
We do not have a logical contradiction here because God is both one and three at the same time, but He is not one and three in the same sense. The three divine persons are distinct in terms of their personal relationships to one another, but not in their essence. All of them are the being of God. They do not have an independent existence—you could not take away any of the three persons and still have God. Rather, the three persons subsist within the one divine nature, coequal in terms of their shared essence.