Our churches teach with common consent that the decree of the Council of Nicaea about the unity of the divine essence and the three persons is true. It is to be believed without any doubt. God is one divine essence who is eternal, without a body, without parts, of infinite power, wisdom, and goodness. He is the maker and preserver of all things, visible and invisible [Nehemiah 9:6]. Yet there are three persons, the Father, the Son, and the Holy Spirit [Matthew 28:19]. These three persons are of the same essence and power. Our churches use the term person as the Fathers have used it. We use it to signify, not a part or quality in another, but that which subsists of itself.
Our churches condemn all heresies [Titus 3:10-11] that assumed that there are two "principles," one Good and the other Evil. They also condemn [those] who contend that God is but one person. They impiously argue that the Word and the Holy Spirit are not distinct persons. (paragraphs 1-6)
[And from the Apology,] We believe and teach that there is one divine, undivided essence. Yet, there are three distinct person, of the same divine essence, and coeternal: father, Son, and Holy Spirit. We have always taught and defended this article. We believe that it has sure and firm testimonies in Holy Scripture that cannot be overthrown. We constantly affirm that those thinking otherwise are outside of Christ's Church, are idolaters, and insult God. (paragraphs 1-2)
Condensed from CONCORDIA: THE LUTHERAN CONFESSIONS, copyright 2005,2006 by Concordia Publishing House. Used by permission. All rights reserved. To purchase a copy of CONCORDIA, call 800-325-3040.