Sadhu engages in...

Expressions researched:
"Sadhu who is always engaged in the service of the Lord, he is sadhu, bhakta" |"sadhu engages in staunch devotional service to the Lord" |"sadhu engages in the highest philanthropic activities for the benediction of all living entities" |"sadhu is always engaged, dedicated to the service of the Lord, he has no other business"

SB Canto 3

There are many instances where a dog got salvation by association with a sādhu, because a sādhu engages in the highest philanthropic activities for the benediction of all living entities.

SB 3.25.21, Purport:

One of the qualifications of a sādhu is that he is very tolerant and is merciful to all fallen souls. He is merciful because he is the well-wisher of all living entities. He is not only a well-wisher of human society, but a well-wisher of animal society as well. It is said here, sarva-dehinām, which indicates all living entities who have accepted material bodies. Not only does the human being have a material body, but other living entities, such as cats and dogs, also have material bodies. The devotee of the Lord is merciful to everyone-the cats, dogs, trees, etc. He treats all living entities in such a way that they can ultimately get salvation from this material entanglement. Śivānanda Sena, one of the disciples of Lord Caitanya, gave liberation to a dog by treating the dog transcendentally. There are many instances where a dog got salvation by association with a sādhu, because a sādhu engages in the highest philanthropic activities for the benediction of all living entities. Yet although a sādhu is not inimical towards anyone, the world is so ungrateful that even a sādhu has many enemies.

SB 3.25.22, Translation:

Such a sādhu engages in staunch devotional service to the Lord without deviation. For the sake of the Lord he renounces all other connections, such as family relationships and friendly acquaintances within the world.

Bhagavad-gita As It Is Lectures

As sādhu is always engaged, dedicated to the service of the Lord, he has no other business.... That is sādhu.

Lecture on BG 4.8 -- Bombay, March 28, 1974:

That is also stated in the Bhagavad-gītā. Sādhur eva sa mantavyaḥ samyag vyavasito hi saḥ (BG 9.30). Who is that man? Api cet su-durācāro bhajate mām ananya-bhāk sādhur eva sa mantavyaḥ. One who is fully engaged. Bhajate mām ananya-bhāk. He has no other engagement. Not partial, some percentage for this purpose, some percentage for that purpose. No. Samyak, wholeheartedly, twenty-four hours engaged in the service of the Lord. He is sādhu. He is sādhu.

Api cet su-durācāraḥ. Even if you find some fault in him. Because sādhu is sādhu-bhūṣaṇaḥ. You cannot find fault in him. Cannot find fault, but even though if you find some fault, but if you find that he is strictly, he's engaged in the service of the Lord, Kṛṣṇa says, he is sādhu. Here it is said, paritrāṇāya sādhūnām. What is the verse number? Yes. Verse number eight. Paritrāṇāya sādhūnām (BG 4.8). As sādhu is always engaged, dedicated to the service of the Lord, he has no other business.... That is sādhu.

Srimad-Bhagavatam Lectures

Sādhu who is always engaged in the service of the Lord, he is sādhu, bhakta. And śāstra. Śāstra means description of the activities of the sādhu and Bhagavān.

Lecture on SB 6.2.12-14 -- Allahabad, January 17, 1971, at Kumbha-mela:

You'll never find any disagreement with the śāstra, sādhu, and guru. Therefore Narottama dāsa Ṭhākura says, sādhu-śāstra-guru-vākya. That is our guidance. Sādhu. If you say Caitanya Mahāprabhu was a sādhu or a devotee, so His words and the words of the scriptures are the same. The sādhu will speak only on the authority of śāstra. And śāstra means the description given by the sādhu. They are correlative. And guru means who follows the sādhu and the śāstra. So these are very instructive. Sādhu who is always engaged in the service of the Lord, he is sādhu, bhakta. And śāstra. Śāstra means description of the activities of the sādhu and Bhagavān. Just like Śrīmad-Bhāgavatam. We are reading the story of Ajāmila. He became a sādhu; therefore his description of his life is imparted here. Prahlāda Mahārāja is sādhu, Dhruva Mahārāja, a sādhu, Ambarīṣa Mahārāja, a sādhu. Formerly the kings were all sādhus, rājarṣi.

1976 Conversations and Morning Walks

There are many instances where a dog got salvation by association with a sādhu, because a sādhu engages in the highest philanthropic activities for the benediction of all living entities.

Room Conversation -- September 4, 1976, Vrndavana:

Prabhupāda: One of the qualifications of a sādhu is that he is very tolerant and is merciful to all fallen souls. He is merciful because he is the well-wisher of all living entities. He is not only a well-wisher of human society, but a well-wisher of animal society as well. It is said here, sarva-dehinām, which indicates all living entities who have accepted material bodies. Not only does the human being have a material body, but other living entities, such as cats and dogs, also have material bodies. The devotee of the Lord is merciful to everyone—the cats, dogs, trees, etc. He treats all living entities in such a way that they can ultimately get salvation from this material entanglement. Śivānanda Sena, one of the disciples of Lord Caitanya, gave liberation to a dog by treating the dog transcendentally. There are many instances where a dog got salvation by association with a sādhu, because a sādhu engages in the highest philanthropic activities for the benediction of all living entities. Yet although a sādhu is not inimical towards anyone, the world is so ungrateful that even a sādhu has many enemies.