Here it will be proper to point out the titles which the Scripture bestows on the Spirit, when it treats of the commencement and entire renewal of our salvation. First, he is called the “Spirit of adoption,” because he is witness to us of the free favor with which God the Father embraced us in his well-beloved and only-begotten Son, so as to become our Fathers and give us boldness of access to him; nays he dictates the very words, so that we can boldly cry, “Abba, Father.” Rom. 8:15; Gal. 4:6
For the same reason, he is said to have “sealed us, and given the earnest of the Spirit in our hearts,” because, as pilgrims in the world, and persons in a manner dead, he so quickens us from above as to assure us that our salvation is safe in the keeping of a faithful God. 2 Cor. 1:22; Eph. 1:13, 14
Hence, also, the Spirit is said to be “life because of righteousness.” But since it is his secret irrigation that makes us bud forth and produce the fruits of righteousness, he is repeatedly described as water. Thus in Isaiah “Ho, every one that thirsteth, come ye to the waters.” Again, “I will pour water upon him that is thirsty, and floods upon the dry ground.” Corresponding to this are the words of our Savior, to which I lately referred, “If any man thirst, let him come unto me and drink.” Sometimes, indeed, he receives this name from his energy in cleansing and purifying, as in Ezekiel, where the Lord promises, “Then will I sprinkle you with clean water, and ye shall be clean.” Rom. 8:10; Isa. 55:1; 44:3; John 7:37; Ezek. 36:25
As those sprinkled with the Spirit are restored to the full vigor of life, he hence obtains the names of “Oil” and “Unction.” John 2:14; 1 John 2:20, 27 On the other hand, as he is constantly employed in subduing and destroying the vices of our concupiscence, and inflaming our hearts with the love of God and piety, he hence receives the name of Fire. Luke 3:16; Acts 11:21
In fine, he is described to us as a Fountain, whence all heavenly riches flow to us; or as the Hand by which God exerts his power, because by his divine inspiration he so breathes divine life into us, that we are no longer acted upon by ourselves, but ruled by his motion and agency, so that everything good in us is the fruit of his grace, while our own endowments without him are mere darkness of mind and perverseness of heart.
Already, indeed, it has been clearly shown, that until our minds are intent on the Spirit, Christ is in a manner unemployed, because we view him coldly without us, and so at a distance from us. Now we know that he is of no avail save only to those to whom he is a head and the first-born among the brethren, to those, in fine, who are clothed with him. To this union alone it is owing that, in regard to us, the Savior has not come in vain. To this is to be referred that sacred marriage, by which we become bone of his bone, and flesh of his flesh, and so one with him (Eph. 5:30), for it is by the Spirit alone that he unites himself to us. By the same grace and energy of the Spirit we become his members, so that he keeps us under him, and we in our turn possess him.
John Calvin, Institutes of the Christian Religion, Book III, Chapter 1, Section 3
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