One of the purposes of yoga is to help the yogi distinguish between their true nature and adhara. Their true nature does exist on a temporary basis within adhara, but it is not the same as the sheaths.
Unlike the yogi’s true divine nature, the adhara is inclined to possess qualities which are imperfect, selfish and fearful. This is suitable and even useful for daily life, but it needs to be recognized that this is not the whole nature of consciousness if the yogi is to progress spiritually. The adhara can be developed and transformed as part of the yogi’s spiritual journey.
Some say that it is important that the adhara is strengthened and purified before a yogi has a spiritual experience and glimpses the subtle world. Otherwise there is a danger that the ego may lose equilibrium, leading to a narcissistic identification with this greater reality. The intention, instead, is to ensure that the adhara is stable and grounded, so that such an experience brings only spiritual progress and greater understanding.