BG Chap 7 - The four types of people who worship Kṛṣṇa

Those who are learned and who engage in their varṇāśrama duties worship the Lord. These souls are not pure devotees but are pious. They can be elevated to pure devotional service by the association of a pure devotee.

(a) ārta – the distressed. They desire relief from suffering like sickness and other material calamities. Gajendra is an example. (b) jijñāsu – the curious. They desire knowledge of the nature of ātmā distinct from the body or knowledge of scriptures with grammar. Śaunaka is an example who approached the Lord to become self realized. (c) arthārthī – desirer of wealth. They desire kingdom and enjoyment in this life and the next with land, money, women etc. They approach Kṛṣṇa and not the demigods. Dhruva is an example. (d) jñānī – the knowledge seeker. The jñānī already knows his self as ātmā and the Lord as Paramātmā. He is niṣkāma because he approaches Kṛṣṇa to gain knowledge and not for fulfilling material desires. Śuka and the Kumāras are examples. Whoever among the four types receives the mercy of the Lord becomes qualified for pure bhakti.

There is also a fifth kind: the appearance of pure bhakti from the very beginning stage, such as Nārada in his previous life, who attained knowledge by the mercy of devotees and developed vaidhi-bhakti step by step.

In this connection it is interesting to note Thakur Bhaktivinode’s enumeration in the
first chapter of Caitanya-śikṣāmṛta of the various general motivations people have to try to please the Lord:

1) Bhaya — out of fear.
2) Āśā — for satisfying material aspirations.
3) Kartavya-buddhi — out of a sense of duty (literally,
“a mentality of what should be done”).
4) Rāga — out of genuine
attraction for the Lord.