Christological transformation in The Mirror of Souls, by Marguerite Porete

A variety of trinitarian references are scattered throughout Porete's treatise, but my concern for this essay is her application of the traditional western Nicene formula with regard to the procession of the three Persons of the Trinity, where the Father is the source without source of all things, the Son proceeds from the Father, and the Spirit proceeds from the Father and the Son. Porete describes this traditional formula as follows:

. . . for God the Father possesses the divine power of Himself without receiving it from any other. He possesses the outpouring of His divine power and gives to His Son the same which He possesses of Himself, and the Son receives it from the Father. So that the Son is born of the Father and so is equal to Him. And from the Father and from the Son is the Holy Spirit, one person in the Trinity. He is not born, but He is. The Son is born of the Father and the Holy Spirit is from the Father and from the Son.4

The Father generates the Son, and the Son, receiving the fullness of the Father, is equal to the Father. The unity of the Trinity consists in the mode of the procession of the Persons: The Holy Spirit proceeds from the Father and the Son, which is the traditional western Christian formula. Thus, Porete can assert that "the Holy Spirit possesses in himself the same divine nature which the Father and the Son possess."5 To repeat, the operative terms in this formula are the generation of the Son from the Father and the procession of the Holy Spirit from both the Father and the Son, so that the Third Person of the Trinity, the Holy Spirit, possesses the fullness of the Father and the Son-that is, the fullness of the unity of the Trinity.

Porete makes precise distinctions among the faculties in the soul, which mirror the procession of the Persons of the Trinity and underscore the claim that the soul is a trinitarian image of God. Her analysis of the will's effects upon the soul's faculties is crucial for her understanding of the nature of the soul. She carefully distinguishes ability, intellect, and understanding.6 A close reading of a portion of the text gives a clear outline of the soul's trinitarian nature:

[A skill in a creature] is a subtle natural ability from which intellect is born, which gives understanding in the Soul . . . . This skill is nimble and tends by nature to attain the fullness of its enterprise, and its enterprise is nothing more than the righteous will of God. This subtle ability is the substance of the Soul; and the intellect is the operation of the soul, and the understanding is the height of the Soul; and such understanding is from substance and from intellect.7

Here we see the trinitarian relation among the faculties of the soul, mirroring the procession of the Persons of the Trinity and showing how the soul is the image of God. Natural ability is the substance of the soul and mirrors the Father; intellect, like the Son, is generated from natural ability; and understanding, reflecting the Holy Spirit, is generated from both natural ability and intellect. These faculties receive divine transformation from the fullness of the Trinity through the work and power of the Holy Spirit, as shown below.