Speaker: Srila Prabhupada
Source:  Wonderful cure for illusion

Sridhara Svami says that “This process is for giving liberation from all kinds of material bondage.” Akhilasya bandhasya muktaye tam anusmara smrtya varnayata.(?) And again Sridhara Svami gives note herewith that “Not only you meditate, but you preach. That will help your meditation.” Just like I am speaking to you. I am meditating simultaneously. Unless I remember, how can I speak to you? Unless my attention is concentrated without any diversion in Krsna subject matter, how can I speak to you? So that is also samadhi. Don’t think that one who is simply sitting, he is in samadhi. One who is preaching, he’s also in samadhi, because he’s thinking of Krsna. Otherwise, how he can talk of Krsna if he does not think of Krsna? Sridhara Swami gives… Tam anusmara smrtya varnayata. Varnayata means “Describe also, preach.” Ity artha. Etac ca vakhyantaram iti madhyama-purusa-prayogah.(?)
So this preaching, sravanam kirtanam, simply hearing of Krsna and chanting of Krsna, preaching of Krsna, is samadhi. And this will make one liberated, akhila-bandha-muktaye, from all kinds of bondage, material bondage.