Consciousness is the symptom of the soul. The Bhagavad-gita (2.62-66) teaches how to control the mind and senses, and (6.5-6) explains that the mind can be one's friend or enemy. The Bhagavad-gita (8.5-6) describes how consciousness at death determines one's future destination. The quality of consciousness determines one's experience and future destination. Purifying consciousness through devotional service is the goal of spiritual practice. Perfect Questions Perfect Answers (Chapters 1 and 5) further clarifies that pure consciousness is Krishna consciousness.