Kṛṣṇa comes Himself, and He manifests His pastimes in Vṛndāvana as cowherd boy—how He is playing with His friends, how He is dealing with Rādhārāṇī, how He is dealing with His parents. Everything is manifested practically just like ordinary human being. But at the same time, whenever there is need, big, big demons, beginning from Pūtanā, when He was only a few months old, He is maintaining His position as God, but dealing with His devotees. This father and mother and friends, lover, all in Vṛndāvana, who are they? They are expansion of Kṛṣṇa. That story we have got in the Kṛṣṇa book, that Brahmā stolen all the cows and calves and cowherd boys. Stolen, and Kṛṣṇa immediately created another set. Then Brahmā understood that "Here is the Supreme Lord, my master." So these Kṛṣṇa's associates, they are all also Kṛṣṇa, expansion of Kṛṣṇa. Ānanda-cinmaya-rasa-pratibhāvitābhis tābhir ya eva nija-rūpatayā kalābhiḥ (Bs. 5.37). We are also expansion of Kṛṣṇa. We living entities, Kṛṣṇa says in the Bhāgavata, mamaivāṁśo, part and parcel.
So samagram, one has to understand actually what is Kṛṣṇa in complete. If you want to that, know that, then this is the process, mayi, mayi āsakta-manaḥ, mayy āsakta-manaḥ (BG 7.1), the mind has to be engaged in Kṛṣṇa, first thing is. Mind. Therefore, Kṛṣṇa manifests Himself in this Deity form. The Deity is Kṛṣṇa Himself. But we cannot concentrate Kṛṣṇa which is not visible. Kṛṣṇa is not visible to the ordinary eyes. Ataḥ śrī-kṛṣṇa na bhaved grāhyam indriyaiḥ (CC Madhya 17.136). God is not perceptible with our this material eyes, our material senses. Ataḥ śrī-kṛṣṇa-nāmādi na . . . even material ears. You are chanting. If you are not spiritually advanced, this chanting of Hare Kṛṣṇa mantra also will not appeal. It will be happening mechanically. But by chanting you will gradually advance, ceto-darpaṇa-mārjanam, then you will understand that this Hare Kṛṣṇa mantra is not different from Kṛṣṇa. The mantra, the sound vibration, is also Kṛṣṇa.