We can engage the tongue for talking about Kṛṣṇa. But those who cannot talk about Kṛṣṇa but talks all nonsense, better stop them talking. That is called mauna. Mauna means "You cannot talk nicely; better you stop talking."
So that is also a kind of vrata, vow. But our process is different: sa vai manaḥ kṛṣṇa-padāravindayor vacāṁsi vaikuṇṭha-guṇānuvarṇane (SB 9.4.18). We do not stop talking, but we talk for preaching Kṛṣṇa consciousness. That is wanted. So there are many, you'll find, they take credit by not talking. Sometimes you go to them and ask some question, they'll write in pencil on the paper, "Will not talk." And what is the meaning of this silence? If I put some questions and you write in paper, what is the difference between talking and writing? I am using the senses. For talking I am using the senses, tongue. Instead of using the sense, tongue, active senses, I am using my hand. So this is also sense gratification. The real fact is that you cannot stop the tongue working. Engage the tongue in Kṛṣṇa consciousness. That is wanted. Don't talk material subject matters. In big, big meetings the politicians, the United Nation, they're talking, but talking all nonsense - simply going there for passing resolution that "Now we have to do this. Then the world will change." No, it will never change. By such kind of foolish talking, it will never change. Better close this United Nation organization because it has not given any practical effect. But talking about Kṛṣṇa, just see how it is giving practical effect. Here you are assembled here from Europe, America and Africa, Canada, and practically all over the world, but you are united nation. You are united nation simply by talking Kṛṣṇa. This is the remedy. And if you keep yourself as American, as Indian, as Canadian, as African, and go to the United Nation and talk for years and years, there will be no more United Nation. It will be . . . More flags will increase. Because this is nonsense talking. It is practical. The United Nation is talking for the last thirty, forty years . . .?