SB 1.7 - Explanation of the ātmārāma verse -II
The word ‘hetu’ means causal – to do something with a motive. There can be three motives for which one does things: bhukti (material enjoyment), siddhi (mystic perfections) and mukti (liberation). There are innumerable varieties of material enjoyment. There are 18 kinds of siddhis. And there are five kinds of liberations. Unalloyed devotional service is unmotivated by any of these desires for personal benefit. When one is free from all these contaminations, he can bring Kṛṣṇa under control. Practice of devotional service in the material field is influenced by the three modes of nature, and above such activities is the transcendental practice called sādhana bhakti.
When this is matured into love for the Lord, the transcendental loving service of the Lord begins gradually developing into nine progressive stages of prema bhakti: rati (attraction), prema (love), sneha (affection), māna (adverse feelings), praṇaya (affinity), rāga (attachment), anurāga (sub attachment or following), bhāva (ecstatic love) and mahābhāva (sublime ecstatic love). Attraction to Kṛṣṇa of devotees in śānta rasa increases up to prema; in dāsya rasa up to rāga; in sakhya rasa up to the point of anurāga; in vātsalya rasa up to the end of anurāga; the gopīs in mādhurya rasa can increase their attraction till mahābhāva. These are some of the meanings of the word bhakti.