CC Ādi 3.11
চারি ভাবের ভক্ত যত কৃষ্ণ তার বশ ॥ ১১ ॥
cāri bhāvera bhakta yata kṛṣṇa tāra vaśa
Servitude [dāsya], friendship [sakhya], parental affection [vātsalya] and conjugal love [śṛṅgāra] are the four transcendental mellows [rasas]. By the devotees who cherish these four mellows, Lord Kṛṣṇa is subdued.
Dāsya, sakhya, vātsalya and śṛṅgāra are the transcendental modes of loving service to the Lord. Śānta-rasa, or the neutral stage, is not mentioned in this verse because although in śānta-rasa one considers the Absolute Truth the sublime great, one does not go beyond that conception. Śānta-rasa is a very grand idea for materialistic philosophers, but such idealistic appreciation is only the beginning; it is the lowest among the relationships in the spiritual world. Śānta-rasa is not given much importance because as soon as there is a slight understanding between the knower and the known, active loving transcendental reciprocations and exchanges begin. Dāsya-rasa is the basic relationship between Kṛṣṇa and His devotees; therefore this verse considers dāsya the first stage of transcendental devotional service.