Just like Hare Kṛṣṇa, Hare Kṛṣṇa, Kṛṣṇa Kṛṣṇa, Hare Hare/ Hare Rāma, Hare Rāma, Rāma Rāma, Hare Hare, this is in the śāstra. So that is potential. Now if we add and subtract something from these sixteen words, that is my manufacture. That will have not the potency. They do not understand it. They are thinking if they can manufacture some new line, adding with Hare Kṛṣṇa, then he becomes particularly noted. But he spoils the whole thing. That is the . . . he does not make any new thing. The new thing he does, he spoils the whole thing.
So Caitanya Mahāprabhu never did so, although He's Kṛṣṇa Himself. He stuck to the point of śāstra. Kṛṣṇa, He is the Supreme Personality of Godhead. He also indicates, yaḥ śāstra-vidhim utsṛjya vartate kāma-kārataḥ na siddhiṁ sāvāpnoti (BG 16.23). He indicates that nobody can give up the injunction of the śāstra. Brahmā-sūtra-padaiś caiva hetumadbhir viniścitaiḥ (BG 13.5). Kṛṣṇa says. He can give. Whatever He says, that is śāstra, that is Veda. But still, He gives reference to the śāstra.
So ācārya's duty is to point out the śāstric injunction. They're already there in the Vedas. His duty is . . . just like there are so many medicines. If you go to a drug shop, all of them are medicines, but the experienced physician, he gives you a medicine which is particularly suitable for you. You cannot say: "Sir, why you are selecting medicine? You can give any one bottle." That is nonsense. Not any one. The particular body, a particular bottle, and a particular medicine which is suitable for you, the experienced physician gives you. He's ācārya.
So you cannot say that, "Everything is medicine; whichever bottle I take, that's all right." No. That's not. This is going on. Yata mata tata patha. Why yata mata tata patha? The particular mata which is suitable for you at a particular time, that should be accepted, not any other mata. So similarly, in this age, in this Kali-yuga, where people are very short-living, duration of life is very short, they are unfortunate, they're very slow, and they take to unauthorized means of religious principles, they're prone to so many disturbances of life . . . therefore this particular medicine for this age, as given by Caitanya Mahāprabhu:
- harer nāma harer nāma harer nāmaiva kevalaṁ
- kalau nāsty eva nāsty eva nāsty eva gatir anyathā
- (CC Adi 17.21)
Prabhu kahe, ihā haite sarva-siddhi haibe tomāra.
So we should take the instruction of Caitanya Mahāprabhu, who has especially incarnated Himself in this age, Kali-yuga. Kalau saṅkīrtana-prāyair yajanti hi su-medhasaḥ. This is the śāstric injunction.