The constitutional position of the living entity is different from the position he takes in the material world. In material consciousness his nature is to try to be the lord of matter, but in spiritual consciousness, Kṛṣṇa consciousness, his position is to serve the Supreme. When the living entity is in material consciousness, he has to take on various bodies in the material world. That is called karma, or varied creation by the force of material consciousness.
(Bhagavad-Gita---8:3---purport).

As long as spirit is within matter, matter can increase as needed; but without the spirit, matter stops increasing. For example, as long as there is spiritual consciousness within the material body of a living entity, the body increases to the required size, but a dead material body, which has no spiritual consciousness, stops increasing. In Bhagavad-gītā (Chapter Two) importance is given to the spiritual consciousness, not the body. The entire cosmic body increased by the same process that we experience in our small bodies.
(Srimad Bhagavatam---3:6:5---purport).

A devotee should always remain ātmavān, or situated in his spiritual position. He should not forget that his main concern is to make advancement in spiritual consciousness, or Kṛṣṇa consciousness, and he should not ignorantly identify himself with the body or the mind.
(Srimad Bhagavatam----3:27:8---purport).

In the presence of the sun, the rays illuminate just like the sun, but when the sunshine is covered by the spell of a cloud, or by māyā, then darkness, the imperfection of perception, begins. Therefore, to get out of the entanglement of the spell of nescience, one has to awaken his spiritual consciousness, or Kṛṣṇa consciousness, in terms of the authorized scriptures.
(Srimad Bhagavatam----3:32:28---purport).

Devotees actually serious about advancing in spiritual life should give up the company of nondevotees and always keep company with devotees. To be too attached to material existence is ignorance because material existence is temporary and miserable. Therefore devotees who are determined to perform tapasya (penances and austerities) to realize the self, and who are determined to become advanced in spiritual consciousness, must give up the company of atheistic nondevotees.
(Srimad Bhagavatam----7:5:37---purport).