54. What is the difference between deity and divinity?
Many who argue against the Trinity are willing to attribute divinity to the Son. Arians, semi-Arians, Socinians, and other Unitarians deny unity of being. To all these people, one must pose this question: Is the Son God in the sense that one can speak of only one God? That decides everything and, faced with that question, everyone must take sides. No one can be saved from it with vague answers.
From: Reformed Dogmatics: Volume One: Theology Proper by Geerhardus Vos; translation from the Dutch supervised and edited by Richard B. Gaffin, Jr. (Bellingham: Lexham Press, 2012-2014), p. 61. Originally published in handwritten form in 1896. First published privately in printed form in 1910.