There are several origins or causes for this compulsive love of Kṛṣṇa, such as Kṛṣṇa Himself, the devotees of Kṛṣṇa, Kṛṣṇa's playing on the flute, etc. The effect is sometimes loving and sometimes stunted.
There are eight transcendental symptoms found in the body during ecstasy, and all of them are possible only by a mixture of the above-mentioned five ecstatic divisions. Without some mixture of these five ecstatic principles, one cannot relish transcendental bliss. The cause or basis for relishing transcendental mellow is exactly what we mean by vibhāva. This vibhāva is divided into two—namely, basic and impetuous. In the Agni Purāṇa the description of vibhāva is given as follows: "The basis from which ecstatic love is born is called vibhāva, which is divided into two—basic and impetuous." In other words, there are two kinds of ecstatic love. The object of basic ecstatic love is Kṛṣṇa and His devotee. Lord Kṛṣṇa is the object of basic ecstatic love, and His pure devotee, a reservoir of such love, is the object of impetuous ecstatic love. Impetuous ecstatic love, then, is that love which develops when one sees an object which reminds him of Kṛṣṇa.
Lord Kṛṣṇa, who is the possessor of inconceivable potencies and qualities of transcendental knowledge and bliss, is the basic cause of ecstatic love. Lord Kṛṣṇa also becomes the reservoir (impetus) of ecstatic love by His different incarnations and expansions. In the Śrīmad-Bhāgavatam there is a statement in connection with the brahma-vimohana-līlā, which demonstrates something of this impetuous feature of ecstatic love. When Brahmā was deluded by Kṛṣṇa, who expanded Himself into so many cowherd boys, calves and cows, Kṛṣṇa's elder brother, Śrī Baladeva (a direct expansion of Kṛṣṇa Himself), felt astonishment and said, "How wonderful it is that my ecstatic love for Kṛṣṇa is again being attracted to so many cowherd boys, calves and cows!" He was struck with wonder by thinking in this way. This is one of the examples in which Kṛṣṇa Himself becomes the object and reservoir of ecstatic love in the impetuous aspect.