The essence of the Sun is childlike in nature, instinctive and uncontrived. The glyph for the Sun is a circle with a dot in the the middle. The dot is your individual soul within the totality of God. When someone bows to you and says “Namaste”, they are acknowledging that point of eternal grace which is the essence of you. To be human is to hold this concept of the eternal. Without that concept, we let go of our connection with divinity. It is not about religion, it is about faith.
In a more mundane way, the Sun in our chart is our vitality and our level of engagement with life. It is our ability to stand up for ourself, and to let the energy flow to us and then from us. The body is represented by the place in the sky where the Sun comes up on the morning we were born, and though the body might not have physical strength, the spirit of the heart is strong if we find our passion.
There is no such thing as a “weak” Sun in the horoscope, though the Hellenistic astrologers will use awful words like “debilitated” and “afflicted”. Those words are extremely misleading, and it would be better if these words were exchanged for something which can resonate with actual human consciousness. There is only the greater understanding of the nature of the Sun in our chart, and the intention we have of living.
The Sun in the horoscope traditionally goes with the father and our self-esteem. If the father aimed for fulfillment in life, then the child will have a good role model. If the father was small in spirit, or overbearing, or insane, then the child needs to look elsewhere for a role model.
All creative works are works of the Sun energy. Like Leo, the Sun is the performer, the one on display, even if it is a quiet display. If the Sun in the horoscope is conjunct to Saturn (the traditional bad guy in the solar system), or square or opposite from it, this does not decree depression, although it could suggest difficulties from the father in the early home. When the Sun is connected with Saturn (or indeed, even in Capricorn), the life energy is centered within creating structure and building.
Our feelings are telling us something when we do not stand up for ourselves, when we believe we are not bright and shiny enough. Whatever is the flavor of your Sun expression, that is how you will stand up and be counted. It matters not at what stage of development you are, as long as your intentions are to respect yourself, and you realize that your own individuality is tempered by your respect for the individuality of others. When we truly learn to stand up for ourselves, we are standing up for everyone else as well.