"There are two more eminent and remarkable images of the Trinity among the creatures. The one
is in the spiritual creation, the soul of man. There is the mind, and the understanding or
idea, and the spirit of the mind as it is called in Scripture, i.e., the disposition, the will or
affection. The other is in the visible creation, viz., the Sun. The father is as the substance
of the Sun. (By substance I don't mean in a philosophical sense, but the Sun as to its internal
constitution.) The Son is as the brightness and glory of the disk of the Sun or that bright and
glorious form under which it appears to our eyes. The Holy Ghost is the action of the Sun which
is within the Sun in its intestine heat, and, being diffusive, enlightens, warms, enlivens and comforts
the world. The Spirit as it is God's Infinite love to Himself and happiness in Himself, is as the
internal heat of the Sun, but as it is that by which God communicates Himself, it is as the
emanation of the sun's action, or the emitted beams of the sun.
"The various sorts of rays of the sun and their beautiful colors do well represent the Spirit.
They well represent the love and grace of God and were made use of for this purpose in the
rainbow after the flood, and I suppose also in that rainbow that was seen round about the throne by
Ezekiel (Ezek. 1:28; Rev. 4:3) and round the head of Christ by John (Rev. 10:1), or the amiable
excellency of God and the various beautiful graces and virtues of the Spirit. These beautiful
colors of the sunbeams we find made use of in Scripture for this purpose, viz., to represent the
graces of the Spirit, as (Ps. 68:13) 'Though ye have lien among the pots, yet shall be as the wings
of a dove covered with silver, and her feathers with yellow gold,' i.e., like the light reflected
in various beautiful colors from the feathers of a dove, which colors represent the graces of the
Heavenly Dove." (Jonathan Edwards, Unpublished Essay on the Trinity).
This imagery might have been suggested by Hebrews 1:1-3,
"God, who at sundry times and in divers manners spake in time past unto the fathers by the prophets, Hath in these last days spoken unto us by his Son, whom he hath appointed heir of all things, by whom also he made the worlds;
Who being the brightness of his glory. . ."
H. C. Hewlett updates the imagery with his usual insight:
"The Father is the living fount of this glory and the
Son is the living stream. The Son is the brightness, the effulgence,
the outshining of the glory, so that the relationship between the
Father and the Son has intimacy like to that between the light and
the ray that streams from it. As is the light, so is the ray, and
neither exists without the other. As are the holiness, the love, and
grace of the Father, so are those of the Son. Indeed all the glories
of God shine forth unchanged in Christ, undimmed in their lustre,
fadeless in their beauty, and constant in their ardor. Moreover,
light may be known only through its own rays, so God may be known
only through Christ. Our Lord in His eternal being, apart altogether
from the changing manifestations of His own majesty, is uniquely and
exclusively the outshining of the glory of God." (H. C. Hewlett, The
Glories of Our Lord, p. 36).
"Objects have three dimensions -- length, breadth, and height - that are distinguishable, but
inseparable, unified in a single object, yet three-dimensional. Our experience of the physical
world always has three dimensions -- space, time, and matter - unified in the being of any physical
object, yet distinguishable. The seeming paradox of three in one is familiar to the human experience of
physical reality." (Thomas C. Oden, The Living God, p. 185).
Memory, Understanding, Will
"Since, then, these three, memory, understanding, will are not three
lives, but one life; nor three minds, but one mind; it follows certainly
that neither are they three substances, but one substance. Since memory,
which is called life, and mind, and substance, is so called in respect
to itself; but it is called memory, relatively to something. And I should
say the same also of understanding and of will, since they are called understanding
and will relatively to something; but each in respect to itself is life,
and mind, and essence. And hence these three are one, in that they are
one life, one mind, one essence; and whatever else they are severally called
in respect to themselves, they are called also together, not plurally,
but in the singular number. But they are three, in that wherein they are
mutually referred to each other; and if they were not equal, and this not
only each to each, but also each to all, they certainly could not mutually
contain each other; for not only is each contained by each, but also all
by each. For I remember that I have memory and understanding, and will;
and I understand that I understand, and will, and remember; and I will
that I will, and remember, and understand; and I remember together my whole
memory, and understanding, and will. For that of my memory which I do not
remember, is not in my memory; and nothing is so much in the memory as
memory itself. Therefore I remember the whole memory. Also, whatever I
understand I know that I understand, and I know that I will whatever I
will; but whatever I know I remember. Therefore I remember the whole of
my understanding, and the whole of my will. Likewise, when I understand
these three things, I understand them together as whole. For there is none
of things intelligible which I do not understand, except what I do not
know; but what I do not know, I neither remember, nor will. Therefore,
whatever of things intelligible I do not understand, it follows also that
I neither remember nor will. And whatever of things intelligible I remember
and will, it follows that I understand. My will also embraces my whole
understanding and my whole memory whilst I use the whole that I understand
and remember. And, therefore, while all are mutually comprehended by each,
and as wholes, each as a whole is equal to each as a whole, and each as
a whole at the same time to all as wholes; and these three are one, one
life, one mind, one essence."
(Augustine, On the Trinity, Book 10, Chapter 11, 18).
"The Word, therefore, is both always in the Father, as He says, 'I am in the Father'; and is
always with God, according to what is written, 'And the Word was with God;' and never separate from the
Father, or other than the Father, since 'I and the Father are one.'...For God sent forth the Word, as
the Paraclete also declares, just as the root puts forth the tree, and the fountain the river, and the
sun the ray...I should not hesitate, indeed, to call the tree the son or offspring of the root, and
the river of the fountain, and the ray of the sun; because every original source is a parent, and
everything which issues from the origin is an offspring. Much more is (this true of) the
Word of God, who has actually received as His own peculiar designation the name of Son. But
still the tree is not severed from the root, nor the river from the fountain, nor the ray from the
sun; nor, indeed, is the Word separated from God...Everything which proceeds from something else
must needs be second to that from which it proceeds, without being on that account separated:
Where, however, there is a second, there must be two; and where there is a third, there must be
three. Now the Spirit indeed is third from God and the Son; just as the fruit of the tree is
third from the root, or as the stream out of the river is third from the fountain, or as the apex of
the ray is third from the sun. Nothing, however, is alien from that original source whence
it derives its own properties. In like manner the Trinity, flowing down from the Father through
intertwined and connected steps, does not at all disturb the Monarchy, whilst it at the same time
guards the state of the Economy."
(Tertullian, Against Praxeas, Chapter VIII).
"A common symbol for the Trinity, the triangle, will help to explain this conception. Picture
a triangle made of gold with each angle taken as one of the three persons. The material out of
which the triangle is made is the common substratum and provides the unity of substance. The
three angles provide the triad since they are identical neither with each other nor with the gold
out of which the figure is made."
(Linwood Urban, A Short History of Christian Thought, p. 60).
Physical analogies suffer from this disadvantage: material things are divisible into parts,
whereas God is simple: "There is but one only, living, and true God, who is infinite in being and
perfection, a most pure spirit, invisible, without body, parts, or passions;..."
Nevertheless such analogies are helpful, because antitrinitarians assume that, because God is one,
the answer to every question about God must be 'one.' But this is like
saying, 'If a man is one, then he can only have one kidney,' or 'If a car
is one, then it can only have one spark plug.' The issue is rank, not divisibility.
"Let me resort here to examples from what we perceive and from what is
familiar. In a house the light from all the lamps is completely interpenetrating, yet each is
clearly distinct. There is distinction in unity and there is unity in distinction. When there
are many lamps in a house there is nevertheless a single undifferentiated light and from all of them
comes the one undivided brightness. I do not think that anyone would mark off the light of one
lamp from another in the atmosphere which contains them all, nor could one light be seen separately
from the others since all of them are completely mingled while being at the same time quite
distinctive." (Pseudo-Dionysius, The Divine Names, Chapter 1, 641B).