Guest: I'm new here. I've never been here before, so forgive me if my questions are naive. But if all it requires is chanting to be pure, then why do you require musical instruments, and an altar and flowers and things of this sort?
Prabhupāda: Hmm?
Viṣṇujana: "If all that is required is chanting Hare Kṛṣṇa, why do we have the pictures and the clothes and the instruments and the altar and Lord Jagannātha?"
Prabhupāda: Because we are personalist. We are not impersonal. This is spiritual varieties. You are talking of no variety. Is it not? You were asking me, "Why there are so many varieties?" This is your plain question.
Guest: Not only that. Why are the heads shaved?
Prabhupāda: That is also another variety. So you want variety-less. Is it not?
Guest: No. I am asking why these are necessary. Why are they necessary?
Prabhupāda: They are not necessary for a person who is advanced. But in the preliminary stage we have such necessities. This creates atmosphere. But at the same time, these varieties are not, I mean to say, material varieties. They are spiritual varieties.
The place where we are trying to approach, Vaikuṇṭha, there the inhabitants are like this. They have got this tilaka, they have got . . . of course, we haven't got four hands, but they have got four hands. There are two hands also. And they are dressed like this. So these things are not material varieties, as much as chanting is not material vibration.
Besides that, any path you follow, you have to follow the regulative principles as they are enacted by authorities. So in our disciplic succession, previous ācāryas, they have advised that you should have your dress like this, you should have your head like this, you . . . so we have to follow that. Mahājano yena gataḥ sa panthāḥ (CC Madhya 17.186).