CC Madhya 22.31
yāhāṅ kṛṣṇa, tāhāṅ nāhi māyāra adhikāra
“Kṛṣṇa is compared to sunshine, and māyā is compared to darkness. Wherever there is sunshine, there cannot be darkness. As soon as one takes to Kṛṣṇa consciousness, the darkness of illusion (the influence of the external energy) will immediately vanish.
In Śrīmad-Bhāgavatam (2.9.34) it is stated:
tad vidyād ātmano māyāṁ yathābhāso yathā tamaḥ
“What appears to be truth without Me is certainly My illusory energy, for nothing can exist without Me. It is like a reflection of a real light in the shadows, for in the light there are neither shadows nor reflections.”
Wherever there is light, there cannot be darkness. When a living entity becomes Kṛṣṇa conscious, he is immediately relieved of all material lusty desires. Lusty desires and greed are associated with rajas and tamas, passion and darkness. When one becomes Kṛṣṇa conscious, the modes of passion and darkness immediately vanish, and then the mode of goodness (sattva-guṇa) remains. When one is situated in the mode of goodness, he can make spiritual advancement and understand things clearly. This position is not possible for everyone. When a person is Kṛṣṇa conscious, he continuously hears about Kṛṣṇa, thinks about Him, worships Him and serves Him as a devotee. If he remains in Kṛṣṇa consciousness in this way, the darkness of māyā certainly will not be able to touch him.