A: People of faith can use astrology just as effectively as anybody. Agnostics can use astrology. Even atheists, if they are willing to suspend disbelief enough to test it for themselves. Astrology does not depend upon or require a particular set of beliefs; it is an open ended, expansive symbol system.
In astrology, there are four elemental kingdoms, each divided into three modes, or phases. Earth represents the body and all things physical; air represents the mind and all things mental; fire represents the creative spirit and all forms of inspiration; water represents the psyche, and all things emotional.
Religion and spirituality are functions of the creative spirit and the emotions. Everybody has a particular religious orientation; even atheism is a religious orientation. Some signs/houses/planets are more inclined to religious faith and to need some sort of connection with God than others.
Sagittarius (mutable fire), and Pisces (mutable water) in particular, have an instinctive grasp of the nature of the Divine, though they have different approaches to experiencing it. A Sagittarian, or someone with a very strong Sagittarius (it should be noted that not everyone with a Sagittarius Sun has a strong Sagittarius, for the Sun’s sign influence can be weakened by house position and challenging aspects) finds it easy to believe in a greater meaning. “You are a child of the Universe, no less than the trees and the stars, you have a right to be here,” is a very Sagittarian concept.
A strong Sagittarian is happy to know that God is good, God is loving, and that God knows and likes the individual personally. Whether or not a person gravitates toward a strong religious community depends on many factors, including childhood religious influence and a philosophical agreement with a particular church or religious faith. Sagittarians enjoy the experience of faith, they find it easy to maintain, and easy to take a philosophical attitude toward ‘negative’ experiences.
Pisceans, and those with a strong emphasis on the 12th House and a powerful Neptune influence, find it easy to surrender their egos into a holistic emotional experience of Unity. Buddhism, meditation, Sufism, Southern Baptists, any path that emphasizes ecstatic union with God, will be attractive to someone with a strongly Piscean orientation, although this is of course subject to modification by other factors.
A strong Piscean who also has strong emphasis in Aquarius, for example, might have a more iconoclastic approach to religion and would likely have a healthy dose of skepticism. This person might be more drawn to secular humanism, or to scientific principles. One with a strongly Capricornian influence might have a strong sense of necessity and focus more on meeting career goals and physical needs; the spiritual side of life might take a back seat. Other emphases can have other results.
Every person is a unique combination of twelve signs, twelve houses and twelve planets/forces, further modified by the inter-relationships between the individual factors (such as aspects, receptions and other refinements). There are near-infinite combinations of factors within an individual’s chart, and there are other considerations that can’t be mapped in the chart, such as gender, sexual orientation, ethnicity and religion.
Astrology provides a tool, a vocabulary of symbols that can be used to develop a holistic understanding of the universe, one including the numinous, the Divine and the emotional and mysterious underpinnings of human motivation. It is possible to use astrology to understand the self and our relationship with the spirit, with God, but always, we choose what to believe. Astrology is a powerful and flexible tool, a map of the universe, but it is not the thing it describes. We are free to become what we choose. Ultimately we include all the forces within our psyche; in that sense, we are created in the image of God. God exists in the individual’s perception of, belief in and relationship to That Which Is. Astrology does not ‘prove’ God, but it does exhibit pattern and meaning, and if we attribute those things to Divine sources, then it can be a reassurance and validation.
If we do not attribute pattern and meaning to a Divine source, then astrology will not convince us of the existence of a God, but it is still a highly useful tool for understanding the self and others.
Religion in the organized sense is not required in order to benefit from the tools and language of astrology, but it is not contradicted by it either. This is a big and complicated question, and there is no easy pat answer.