Reporter (1): Swamiji, does this chanting of mantra brings purity or following of your four instructions or regulations which you have told, or both?
Prabhupāda: Oh, yes. Yes. Yes. It purifies the heart, yes, the core of the heart. Ceto-darpaṇa-mārjanam (CC Antya 20.12). This is the effect of chanting, because everything we are doing on account of dirty heart, so everything is dirty. So if you purify your heart, then everything becomes clear.
Reporter (1): How long does it take to purify ourself?
Prabhupāda: It takes.... Just like if the dirty things are very fixed up, it takes little more time. Otherwise it takes little time.