Arthur E. Waite - The Pictorial Key to the Tarot :
A winged angel, with the sign of the sun upon his forehead and on his breast the square and triangle of the septenary. I speak of him in the masculine sense, but the figure is neither male nor female. It is held to be pouring the essences of life from chalice to chalice. It has one foot upon the earth and one upon waters, thus illustrating the nature of the essences.
A direct path goes up to certain heights on the verge of the horizon, and above there is a great light, through which a crown is seen vaguely. Hereof is some part of the Secret of Eternal Life, as it is possible to man in his incarnation. All the conventional emblems are renounced herein.
So also are the conventional meanings, which refer to changes in the seasons, perpetual movement of life and even the combination of ideas. It is, moreover, untrue to say that the figure symbolizes the genius of the sun, though it is the analogy of solar light, realized in the third part of our human triplicity.
It is called Temperance fantastically, because, when the rule of it obtains in our consciousness, it tempers, combines and harmonises the psychic and material natures. Under that rule we know in our rational part something of whence we came and whither we are going.
P. D. Ouspensky – The Symbolism Of The Таrot :
An angel in a white robe, touching earth and heaven, appeared. His wings were flame and a radiance of gold was about his head. On his breast he wore the sacred sign of the book of the Tarot--a triangle within a square, a point within the triangle; on his forehead the symbol of life and eternity, the circle.
In one hand was a cup of silver, in the other a cup of gold and there flowed between these cups a constant, glistening stream of every colour of the rainbow. But I could not tell from which cup nor into which cup the stream flowed.
In great awe I understood that I was near the ultimate mysteries from which there is no return. I looked upon the angel, upon his symbols, his cups, the rainbow stream between the cups,--and my human heart trembled with fear and my human mind shrank with anguish and lack of understanding.
"Yes", said the voice, "this is a mystery that is revealed at Initiation. 'Initiation' is simply the revealing of this mystery in the soul. The Hermit receives the lantern, the cloak and the staff so that he can bear the light of this mystery.
"But you probably came here unprepared. Look then and listen and try to understand, for now understanding is your only salvation. He who approaches the mystery without complete comprehension will be lost.
"The name of the angel is Time. The circle on his forehead is the symbol of eternity and life. Each life is a circle which returns to the same point where it began. Death is the return to birth. And from one point to another on the circumference of a circle the distance is always the same, and the further it is from one point, the nearer it will be to the other.
"Eternity is a serpent, pursuing its tail, never catching it.
"One of the cups the angel holds is the past, the other is the future. The rainbow stream between the cups is the present. You see that it flows both ways.
"This is Time in its most incomprehensible aspect.
"Men think that all flows constantly in one direction. They do not see that everything perpetually meets and that Time is a multitude of turning circles. Understand this mystery and learn to discern the contrary currents in the rainbow stream of the present.
"The symbol of the sacred book of the Tarot on the angel's breast is the symbol of the correlation of God, Man and the Universe.
"The triangle is God, the world of spirit, the world of ideas. The point within the triangle is the soul of man. The square is the visible world.
"The consciousness of man is the spark of divinity, a point within the triangle of spirit. Therefore the whole square of the visible universe is equal to the point within the triangle.
"The world of spirit is the triangle of the twenty-one signs of the Tarot. The square represents fire, air, water and earth, and thus symbolises the world.
"All this, in the form of the four symbols, is in the bag of the Fool, who himself is a point in a triangle. Therefore a point without dimension contains an infinite square".