tal-laká¹£aṇÄni vÄcyante nÄnÄ-mata-bhedÄt
tat - of it (devotional service); laká¹£aṇÄni - the characteristics; vÄcyante - are enunciated; nÄnÄ - various; mata - of theories; bhedÄt - according to the differences.
Now the characteristics of devotional service will be described according to various authoritative opinions.
In the ÅšrÄ«mad-BhÄgavatam (7.5.23), PrahlÄda MahÄrÄja very clearly states what the essential activities of devotional service are:
Å›ravaṇaá¹ kÄ«rtanaá¹ viṣṇoḥ smaraṇaá¹ pÄda-sevanam
arcanaá¹ vandanaá¹ dÄsyaá¹ sakhyam Ätma-nivedanam
"Devotional service consists of (1) hearing about the Lord, (2) chanting His glories, (3) remembering Him, (4) serving and meditating upon His lotus feet, (5) worshiping Him, (6) praying to Him, (7) thinking oneself His eternal servant, (8) becoming His friend, and (9) surrendering everything to Him."
One should surrender to the Lord as much as an animal purchased from the market surrenders to its master. Such an animal never thinks of his maintenance because he knows that his master will look after him. A soul totally surrendered to the Supreme Lord is similarly never anxious for his maintenance. ÅšrÄ«la SanÄtana GosvÄmÄ« gives further symptoms of full surrender in his Hari-bhakti-vilÄsa (11.417):
ÄnukÅ«lyasya saá¹…kalpaḥ prÄtikÅ«lyasya varjanam
raká¹£iá¹£yatÄ«ti viÅ›vÄso goptá¹›tve varaṇaá¹ tathÄ
Ätma-niká¹£epa-kÄrpaṇye á¹£aá¸-vidhÄ Å›araṇÄgatiḥ
"The six divisions of surrender are: accepting those things favorable to devotional service, rejecting unfavorable things, the conviction that Kṛṣṇa will give protection, accepting the Lord as one's guardian or master, full self-surrender, and humility." NÄrada will gradually explain these principles of devotion in the remaining sÅ«tras.
