Srila Bhakti Rakshaka Sridhar Dev Goswami Maharaj’s explanation of Srimad Bhagavatam sloka
śravaṇaṁ kīrtanaṁ viṣṇoḥ,
smaraṇaṁ pāda-sevanam
arcanaṁ vandanaṁ dāsyaṁ,
sakhyam ātma-nivedanam.
iti puṁsārpitā viṣṇau,
bhaktiś cen nava-lakṣaṇā
kriyeta bhagavaty addhā
tan manye ‘dhītam uttamam
“Hearing about Kṛṣṇa, chanting Kṛṣṇa’s glories, remembering Kṛṣṇa, serving Kṛṣṇa’s lotus feet, worshipping Kṛṣṇa’s transcendental form, offering prayers to Kṛṣṇa, becoming Kṛṣṇa’s servant, considering Kṛṣṇa as one’s best friend, and surrendering everything to Kṛṣṇa – these nine processes are accepted as pure devotional service.” (S-B, 7.5.23-24)
“Hearing, speaking about, and remembering Kṛṣṇa, serving His lotus feet, worshipping His Deity form, praying, becoming His servant, cultivating His friendship, and surrendering to Him utterly are the nine processes of devotion. One who cultivates these nine processes of devotion, offering himself completely to Kṛṣṇa, can easily attain the ultimate goal of life.”
What are the forms of sādhana? What are the means to attain kṛṣṇa-bhakti? How can we revive our innate love for Kṛṣṇa? We are told to hear about Him, to talk about Him, to meditate upon Him, to praise Him, and so on. But in his commentary on this verse, Śrīdhara Swāmī has explained that we should not anticipate what benefit we shall derive from śravaṇaṁ kīrtanaṁ, hearing or talking or thinking about Kṛṣṇa. Rather we should pray: “May whatever service I do go to my Lord. I am not the enjoying party – He is the sole proprietor.”
All these functions (śravaṇaṁ, kīrtanaṁ etc.) will be considered devotion only if one condition is fulfilled; otherwise, they may be karma, jñāna, yoga, or anything else. They may even be vikarma, polluted misdeeds. One condition must be there to ensure that all these different forms of devotional activity are actually bhakti: We are His property; we are not the owners of any wealth or property. We must think: “My Lord is the possessor and I am in His possession. Everything is His property.” (LSFTLS, p 14-5) + (see also śloka 13)