The "Solar Angel" represents the human Soul or 'higher self.' Each Monad or 'Spark of God' reflects itself on the causal plane as the soul which in turn reflects itself on the physical plane as the human personality. Its nature, too, is fire and is represented in the painting by the 'Causal Body', the oval, surrounded by the fire of the Soul.
The "Solar Angel" represents our true nature. All of us are souls in incarnation. Our true nature is an individualized part of one great angel whose name is Lucifer. I am often asked during interviews about the nature of Lucifer. The common idea is that Lucifer is Satan, the devil. Nothing could be further from the truth. Lucifer, the Light-bringer, embodies the whole of humanity. Lucifer is a great angelic being, the Oversoul of all the souls of humanity. The fall of Lucifer from heaven, in the Christian Bible, is a symbolic account of the descent into incarnation (some eighteen and a half million years ago, according to the esoteric teachings) of the human souls for the first time.
The human souls, according to the Plan of the Logos, descended, fell, as it were, from Paradise, where they are perfect, into flesh, into the human kingdom, and the evolution of the human kingdom began all these millions of years ago. The story of Adam and Eve in the Christian Bible symbolizes this descent from Paradise. It was nto by accident but the result of the evolutionary Plan. It is as fire because that is the nature of the solar reality. We are souls, perfected Beings, perfect expressions or emanations from the Planetary Logos Whose nature is fire.