Sādhu means saintly person. Titikṣavaḥ kāruṇikāḥ suhṛdaḥ sarva-dehinām (SB 3.25.21).
He's tolerant, he's very kind to everyone, and he's friend to all living entities. He has no enemy, or he is nobody's enemy. And he's peaceful. These are some of the qualification. There are twenty-six qualification in details. But these are some of the qualification. And in the Bhagavad-gītā you'll find the description of a sādhu, saintly person, is given by the Lord Himself. And what is that? He says:
- api cet su-durācāro
- bhajate mām ananya-bhāk
- sādhur eva sa mantavyaḥ
- samyag vyavasito hi saḥ
- (BG 9.30)
He said: "Arjuna, a person who is cent percent engaged in Kṛṣṇa consciousness, he might be externally, ephemerally seen to be addicted to some bad habits. Still, you should consider him to be a saint." "You should consider him to be saint."
What is that? Now, suppose we have contaminated so many things in our material life. There are, in a material calculation, there are so many things which are the list. One list is for morality and another list is for immorality. I do not wish to discuss this list because in . . . for a person which is immorality, for another person it is not immorality—it is morality. Just like according to our conception, hindu conception, drinking of wine is immoral, whereas in your country drinking of wine is not immoral; it is common thing. Of course . . . so according to time, class, place, the conception of morality and immorality are different. But there is a, a sense of immorality and morality in everywhere. That is a fact.
So Kṛṣṇa says that, "Even if you see a person immoral, but he is completely engaged in Kṛṣṇa consciousness, then it should be concluded that he is a saint. He's a saintly person." That is the description given by Kṛṣṇa of sādhu. Api cet su-durācāro bhajate mām ananya-bhāk, sādhur eva sa mantavyaḥ (BG 9.30). So in other words, He says, "Any person who is engaged in Kṛṣṇa consciousness, never mind he might have something externally immoral habits due to his past association—it doesn't matter."
So some way or other, one should be Kṛṣṇa conscious. And then, gradually, he will become a saintly person. As he goes on executing this process of Kṛṣṇa consciousness, then, with his advancement, he becomes a perfect saint. That you'll find in the Bhagavad-gītā. And how Kṛṣṇa says that even if he's externally a little immoral . . . of course, a devotee, or a person who is Kṛṣṇa conscious, he's never immoral. But it may be that due to his past association he may appear to be immoral or he may fall down. Fall down. Due to habits, we may sometimes fall down.