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.
So saṅga upaṅgāstra-pārṣadam. Astra, astra means weapon. So saṅga . . . because when God incarnates, He has got two business: paritrāṇāya sādhūnāṁ vināśāya ca duṣkṛtām (BG 4.8). So one business is to give protection to the devotee and to annihilate the duṣkṛta, those who are sinful. So for annihilating, it requires weapon, śaṇkha, cakra, gadā, padma. Lord Rāmacandra has got bows and arrows, and Kṛṣṇa has got Sudarśana-cakra. But here it is said, saṅga-upaṅga-astra. What is that astra, weapon? Caitanya Mahāprabhu has no astra. Seemingly there's no . . . but this is astra, this hari-saṅkīrtana. This is astra. In the Kali-yuga there is no profit by killing them. They're already killed. So therefore this is the astra. To kill the miscreants this is astra, this hari-saṅkīrtana. If they simply chant Hare Kṛṣṇa, this is astra that will kill all their sinful reaction of life; they'll become devotee. This is astra. Now it is not required the bows and arrows or . . . because they're already dead, because they have no conception of God. Simply fighting how to avoid God, this is their business. It is very difficult to convince them about the existence of . . . they're seeing every moment there is existence of God, but they're so stubborn, so much bewildered by māyā, they'll not. So under the circumstances Caitanya Mahāprabhu, He's therefore called namo mahā-vadānyāya, most munificent incarnation. Why? Kṛṣṇa-prema-pradāya te (CC Madhya 19.53). Even without understanding Kṛṣṇa, simply by chanting Hare Kṛṣṇa mantra they become ecstatic for love of Kṛṣṇa. This is Caitanya Mahāprabhu's benediction: no qualification, but if he simply chants Hare Kṛṣṇa mantra he'll be ecstatic. Kṛṣṇa-prema-pradāya te.