Read Bhagavatam. Pronounce the verses very nicely. Therefore we're repeating. You hear the records and try to repeat. Simply by chanting the mantra you'll be purified. Simply by chant…

Even you do not understand a single word of it, simply if you chant, this vibration has got such power. Srnvatam sva-kathah krsnah punya-sravana-kirtanah [SB 1.2.17]. If you simply chant and vibrate this verse…, these verses, these slokas, it is punya-sravana-kirtanah.

There is no question of understanding. Punya-sravana-kirtanah. Punya means pious, and sravana means hearing, and kirtana means chanting. One who is chanting this verse and one who is hearing this verse, he is becoming pious automatically. To become pious one has to endeavor so much: do this, do that. But if you simply hear these verses of Srimad-Bhagavatam, Bhagavad-gita…

Therefore, as a rigid principle, in every temple there should be class for hearing and chanting. Without hearing and chanting, to become leader it is impossible. You can become leader in the material world, but not in the spiritual world.

(From Srila Prabhupada's class on Srimad-Bhagavatam 1.8.22 — April 14, 1973, Los Angeles)