A pure devotee's attraction to Kṛṣṇa in conjugal love is called devotional service in conjugal love. Although such conjugal feelings are not at all material, there is some similarity between this spiritual love and material activities. Therefore, persons who are interested only in material activities are unable to understand this spiritual conjugal love, and these devotional reciprocations appear very mysterious to them. Rūpa Gosvāmī therefore describes conjugal love very briefly.
The impetuses of conjugal love are Kṛṣṇa and His very dear consorts, such as Rādhārāṇī and Her immediate associates. Lord Kṛṣṇa has no rival: no one is equal to Him, and no one is greater than Him. His beauty is also without any rival, and because He excels all others in the pastimes of conjugal love, He is the original object of all conjugal love.
In the Gīta-govinda by Jayadeva Gosvāmī one gopī tells her friend: "Kṛṣṇa is the reservoir of all pleasure within this universe. His body is as soft as the lotus flower. And His free behavior with the gopīs, which appears exactly like a young boy's attraction to a young girl, is a subject matter of transcendental conjugal love." A pure devotee follows in the footsteps of the gopīs and worships the gopīs as follows: "Let me offer my respectful obeisances to all the young cowherd girls, whose bodily features are so attractive. Simply by their beautiful attractive features they are worshiping the Supreme Personality of Godhead, Kṛṣṇa." Out of all the young gopīs, Śrīmatī Rādhārāṇī is the most prominent.
The beauty of Śrīmatī Rādhārāṇī is described as follows: "Her eyes defeat the attractive features of the eyes of the cakorī bird. When one sees the face of Rādhārāṇī, he immediately hates the beauty of the moon. Her bodily complexion defeats the beauty of gold. Thus, let us all look upon the transcendental beauty of Śrīmatī Rādhārāṇī." Kṛṣṇa's attraction for Rādhārāṇī is described by Kṛṣṇa Himself thus: "When I create some joking phrases in order to enjoy the beauty of Rādhārāṇī, Rādhārāṇī hears these joking words with great attention; but by Her bodily features and counter words She neglects Me. And I even possess unlimited pleasure by Her neglect of Me, for She becomes so beautiful that She increases My pleasure one hundred times." A similar statement can be found in Gīta-govinda, wherein it is said that when the enemy of Kaṁsa, Śrī Kṛṣṇa, embraces Śrīmatī Rādhārāṇī, He immediately becomes entangled in a loving condition and gives up the company of all other gopīs.
In the Padyāvalī of Rūpa Gosvāmī it is stated that when the gopīs hear the sound of Kṛṣṇa's flute, they immediately forget all rebukes offered by the elderly members of their families, their defamation and the harsh behavior of their husbands. Their only thought is to go out in search of Kṛṣṇa. When the gopīs meet Kṛṣṇa, the display of their exchanging glances as well as their joking and laughing behavior is called anubhāva, or sub-ecstasy in conjugal love.
In the Lalita-mādhava, Rūpa Gosvāmī explains that the movements of Kṛṣṇa's eyebrows are just like the Yamunā, and the smiling of Rādhārāṇī is just like the moonshine. When the Yamunā and the moonshine come in contact on the bank of the river, the water tastes just like nectar, and drinking it gives great satisfaction. It is as cooling as piles of snow. Similarly, in the Padyāvalī, one constant companion of Rādhārāṇī says, "My dear moon-faced Rādhārāṇī, Your whole body appears to be very content, yet there are signs of tears in Your eyes. Your speech is faltering, and Your chest is also heaving. By all these signs I can understand that You must have heard the blowing of Kṛṣṇa's flute, and, as a result of this, Your heart is now melting."
In the same Padyāvalī there is the following description, which is taken as a sign of frustration in conjugal love. Śrīmatī Rādhārāṇī said, "Dear Mr. Cupid, please do not excite Me by throwing your arrows at My body. Dear Mr. Air, please do not arouse Me with the fragrance of flowers. I am now bereft of Kṛṣṇa's loving attitude, so under the circumstances, what is the use of My sustaining this useless body? There is no need for such a body by any living entity." This is a sign of frustration in ecstatic love for Kṛṣṇa.
Similarly, in Dāna-keli-kaumudī, Śrīmatī Rādhārāṇī, pointing to Kṛṣṇa, says, "This clever boy of the forest has the beauty of a bluish lotus flower, and He can attract all the young girls of the universe. Now after giving Me a taste of His transcendental body, He has enthused Me, and it is more than I can tolerate. I am now feeling like a female elephant who has been enthused by a male elephant!" This is an instance of jubilation in ecstatic love with Kṛṣṇa.
Steady ecstasy of conjugal love is the original cause of bodily enjoyment. In the Padyāvalī this original cause of union is described when Rādhārāṇī tells one of Her constant companions: "My dear friend, who is this boy whose eyelids, dancing constantly, have increased the beauty of His face and attracted My desire for conjugal love? His ears are decorated with the buds of aśoka flowers, and He has dressed Himself in yellow robes. By the sound of His flute, this boy has already made Me impatient."
The conjugal love of Rādhā-Kṛṣṇa is never disturbed by any personal consideration. The undisturbed nature of the conjugal love between Rādhā and Kṛṣṇa is described thus: "Just a little distance away from Kṛṣṇa was Mother Yaśodā, and Kṛṣṇa was surrounded by all of His friends. In front of His eyes there was Candrāvalī, and, at the same time, on a chunk of stone in front of the entrance to Braja, there was standing the demon known as Vṛṣāsura. But even in such circumstances, when Kṛṣṇa saw Rādhārāṇī standing just behind a bush of many creepers, immediately His beautiful eyebrows moved just like lightning towards Her."
Another instance is described as follows: "On one side of the courtyard the dead body of Śaṅkhāsura was lying, surrounded by many jackals. On another side were many learned brāhmaṇas who were all self-controlled. They were offering nice prayers, which were as soothing as the cool breeze in summer. In front of Kṛṣṇa, Lord Baladeva was standing, causing a cooling effect. But even amidst all these different circumstances of soothing and disturbing effects, the lotus flower of ecstatic conjugal love that Kṛṣṇa felt for Rādhārāṇī could not wither." This love of Kṛṣṇa for Rādhārāṇī is often compared to a blooming lotus: the only difference is that Kṛṣṇa's love remains ever-increasingly beautiful.