CC Madhya 24.352
vidhi-rāga-mārge ‘sādhana-bhakti’ra vidhāna
kṛṣṇera svarūpa-gaṇera — of Lord Kṛṣṇa in His various expansions; sakala — all; haya — there is; jñāna — knowledge; vidhi-rāga-mārge — in the process of devotional service under regulative principles or in spontaneous love; sādhana bhaktira vidhāna — the authorized means of executing devotional service.
By reading these instructions to Sanātana Gosvāmī, one will become fully aware of Lord Kṛṣṇa’s various expansions and the process of devotional service according to the regulative principles and spontaneous love. Thus everything can be fully known.