God has many names. It is not that you have to chant only "Kṛṣṇa." No. If you have got any other name of God . . . must be God's name. But they do not believe in God. Generally they think there is no God, or if there is God, God is dead. Something like that. And I don't think there is any definite, definitive name in any other religious system. It is only in the Vedic system there is name. So anyway, if somebody thinks that "This 'Kṛṣṇa' is Indian name. Why shall I chant 'Kṛṣṇa'?" You chant any other name, but it must be God's name. Then it will be effective. Just like immediately chanted "Nārāyaṇa." Not that one has to chant "Kṛṣṇa." "Nārāyaṇa" will do. "Govinda" will do. Must be God's name, because God and God's names . . . there are sahasra, one thousand, Viṣṇu-stotra. God has many names, hundreds and thousands. So any name you prefer, you chant, you'll get the result. This is the process. God, factually, He has no name. How many names you will remember? But His names are given according to His activities. Kṛṣṇa, Kṛṣṇa is the best name. Why? That Kṛṣṇa means "all-attractive." This name can attract everyone. This is the most perfect. Although God has many names, out of many names the Kṛṣṇa name is mukhya, or the primary.
So Caitanya Mahāprabhu has introduced Kṛṣṇa name, kṛṣṇa-varṇam. Caitanya Mahāprabhu's identification is given in the Śrīmad-Bhāgavatam, kṛṣṇa-varṇam, kṛṣṇam varṇa iti, iti kṛṣṇa-varṇam. He is always chanting "Kṛṣṇa." He's Kṛṣṇa, kṛṣṇa-varṇaṁ tviṣākṛṣṇaṁ (SB 11.5.32). The incarnation of Caitanya Mahāprabhu is described in the Eleventh Canto, perhaps Fifth Chapter. He's described. He has recommended in the śāstra that in the Kali-yuga this incarnation, this form of God, should be worshiped. What is that? That is here: kṛṣṇa-varṇaṁ tviṣākṛṣṇaṁ. He is always chanting "Kṛṣṇa," and He's Kṛṣṇa. He belongs to the category of Kṛṣṇa, kṛṣṇa-varṇam. Kṛṣṇa-varṇaṁ tviṣākṛṣṇaṁ. But in this age His bodily complexion is not blackish. Yellowish. Kṛṣṇa-varṇaṁ tviṣākṛṣṇaṁ saṇgopaṅgāstra-pārṣadam (SB 11.5.32): accompanied by His associates, just like there is Nityānanda, there is Advaita, there is Gadādhara.