The hierarchy is:
- Word, and
In Zoroastrianism, a person's choice of spirit is the fundamental choice a person can make. Before the age of reason, fifteen years of age, parents, family members, elders, teachers and other centres on influence, assist in shaping a person's spirit. After the age of reason, Zoroastrian tradition would make a person entirely responsible for the choice of her or his spirit and from there, responsible for every thought, word and deed.
Perhaps the concept of free will applies to the greatest degree to a person's choice of spirit - it is that choice over which a person has the greatest amount of control and which is least subject to circumstance. The fundamental choice in spirit determines the nature of a person's character, which is also the character of her or his soul - that person's way of being.
A human being's fundamental choice of spirit is between a 'bright' and 'dark' spirit - put differently, a good and not-good (bad) spirit - the duality and dichotomy of the spirit that is a fundamental feature of creation. A defining feature of goodness is beneficence, while a defining feature of not-goodness is its dual opposite, harm.
A bright spirit is also peaceful and constructive, while a dark spirit is aggressive and destructive. As such a bright spirit is perpetually vulnerable to the aggression and destructiveness of a dark spirit and must therefore be continually reaffirmed by a person. The process of securing a bright spirit against the constant inroads by a dark spirit is outlined in chapter 30 of the Gathas, the hymns of Zarathushtra (Zarathustra/Zoroaster).
An admittedly imperfect way viewing the difference between the spirit and thought, is that the spirit is not subject to the time-space continuum of the material world, gaetha. A thought, word and deed have coordinates of time and space and are an indelible feature of the time-space continuum. The spirit is not similarly subject to the gaetha existence. While thoughts, words and deeds require consciousness, the spirit while nurtured during consciousness, survives the end of consciousness.
Alternatively, a person's spirit is a way of being which leads to a way of thinking (a philosophy), a way of speaking and eventually a way of living - at which point it becomes a way of life. Without consciousness and a material body, the spirit cannot be manifest as a way of life.
Depending on the spirit a person chooses, she or he becomes cheerful or angry, constructive or destructive, helpful or harmful, honest or dishonest, loyal or unfaithful, healthy or unhealthy, serene or agitated, peaceful or conflicted, holistic or imbalanced.
Organized as a way in which an entire community chooses to believe, the collective spiritual beliefs if you will, express its beliefs and perform its rites of passage in ritual - Zoroastrianism becomes a religion.