John Calvin from "The Institutes of the Christian Religion"

From Book One, Chapter Thirteen

THE UNITY OF THE DIVINE ESSENCE IN THREE PERSONS TAUGHT, IN SCRIPTURE, FROM THE FOUNDATION OF THE WORLD.

This chapter consists of two parts.

The former delivers the orthodox doctrine concerning the Holy Trinity. This occupies from sec. 1-21,and may be divided into four heads; the first, treating of the meaning of Person, including both the term and the thing meant by it, sec. 2-6; the second, proving the deity of the Son, sec. 7-13;the third, the deity of the Holy Spirit, sec. 14 and 15; and the fourth, explaining what is to be held concerning the Holy Trinity.

The second part of the chapter refutes certain heresies which have arisen, particularly in our age, in opposition to this orthodox doctrine. This occupies from sec. 21 to the end.