"Brahmaji wanted to create the whole cosmic situation as it was in the previous millennium, and because, in the last devastation, knowledge of the Absolute Truth was altogether erased from the universe, he desired that the same knowledge again be renovated; otherwise there would be no meaning in the creation. Because transcendental knowledge is a prime necessity, the ever-conditioned souls are given a chance for liberation in every millennium of creation.
This mission of Brahmaji was fulfilled by the grace of the Lord when the four sanas, namely Sanaka, Sanat-kumara, Sanandana and Sanatana, appeared as his four sons. These four sanas were incarnations of the knowledge of the Supreme Lord, and as such they explained transcendental knowledge so explicitly that all the sages could at once assimilate this knowledge without the least difficulty. By following in the footsteps of the four Kumaras, one can at once see the Supreme Personality of Godhead within oneself."
Srimad-Bhagavatam 2:7:5
"Although Brahma created the principles of nescience as a matter of necessity for those living entities who were destined to ignorance by the will of he Lord, he was not satisfied in performing such a thankless task. He therefore created four principles of knowledge: sankhya, or empirical philosophy for the analytical study of material conditions; yoga or mysticism for liberation of the pure soul from material bondage; vairagya, the acceptance of complete detachment from material enjoyment in life to elevate oneself to the highest spiritual understanding; and tapas, or the various kinds of voluntary austerities performed for spiritual perfection.
Brahma created the four great sages Sanaka, Sananda, Sanatana and Sanat to entrust them with these four principles of spiritual advancement, and they inaugurated their own spiritual party, or sampradaya, known as the Kumara-sampradaya, or later on as the Nimbaraka-sampradaya, for the advancement of bhakti. All of these great sages became great devotees, for without devotional service to the Personality of Godhead one cannot achieve success in any activity of spiritual value."
Srimad-Bhagavatam 3:12:4
"The specific importance of the Kumaras is that they were brahmacaris, living the life of celibacy from birth. They kept themselves as small children about four or five years old because by growing into youth one's senses sometimes become disturbed and celibacy becomes difficult. The Kumaras therefore purposefully remained children because in a child's life the senses are never disturbed by sex."
Srimad-Bhagavatam 4:22:12
"So these four Kumaras--kumaras means unmarried brahmacaris--they were sons of Brahma. Because in the beginning Brahma begot so many sons, and each of them were asked to increase the population. Sanaka, Sananda, Sanatana, they were also requested by their father to increase population, but they refused. They said, "No, we are not going to be entangled in these material affairs. We shall remain kumaras, brahmacari, and preach the glories of God," by which Brahma was angry. And while he was angry, from his anger Rudra, Siva, was produced, and Lord Siva is therefore supposed to be son of Brahma. So these four Kumaras, they represented the knowledge opulence of the Supreme Lord."
Srila Prabhupada Lecture on Caitanya-caritamrta, 12-31-66, New York
"As in the modern day there are many champions in sports, so in bygone days there were many learned scholars in India who were champions in learning. One such person was Kesava Kasmiri, who came from the state of Kashmir. He traveled all over India and at last came to Navadvipa to challenge the learned scholars there. Unfortunately he could not conquer the learned scholars in Navadvipa, for he was defeated by the boy scholar Caitanya Mahaprabhu. Later he understood that Caitanya Mahaprabhu is none other than the Supreme Personality of Godhead. Thus he surrendered unto Him and later became a pure Vaisnava in the sampradaya of Nimbarka. He wrote Kaustubha-prabha, a commentary on the Vedanta commentary of the Nimbarka-sampradaya, which is known as the Parijata-bhasya.
The Bhakti-ratnakara mentions Kesava Kasmiri and lists his predecessors in the disciplic succession of the Nimbarka-sampradaya: (1) Srinivasa Acarya, (2) Visva Acarya, (3) Purusottama, (4) Vilasa, (5) Svarupa, (6) Madhava, (7) Balabhadra, (8) Padma, (9) Syama, (10) Gopala, (11) Krpa, (1 2) Deva Acarya, (13) Sundara Bhatta, (14) Padmanabha, (15) Upendra, (16) Ramacandra, (17) Vamana, (18) Krsna, (19) Padmakara, (20) Sravana, (21) Bhuri, (22) Madhava, (23) Syama, (24) Gopala, (25) Balabhadra, (26) Gopinatha, (27) Kesava, (28) Gokula and (29) Kesava Kasmiri. It is stated in the Bhakti-ratnakara that Kesava Kasmiri was a favorite devotee of mother Sarasvati, the goddess of learning. By her grace he was an extremely influential scholar, and he was the greatest champion among all the scholars in the four corners of the country. Therefore he got the title dig-vijayi, which means "one who has conquered everyone in all directions." He belonged to a very respectable brahmana family of Kashmir. Later, by the order of Sri Caitanya Mahaprabhu, he gave up the profession of winning championships and became a great devotee. He joined the Nimbarka-sampradaya, one of the Vaisnava communities of the Vedic culture."
Caitanya-caritamrta, Adi lila 16:25
Bhaktivedanta Book Trust. HDG A.C. Bhaktivedanta Swami Srila Prabhupada.
Nimbarka identified the Supreme Brahman as the divine couple, Radha-Krishna. His philosophy was Dvaitadvaita, oneness and difference, a position between Sankara's monism and Madhva's purified dualism. Sri Nimbarka treated the unity of existence and the differentiations as equally true, without putting emphasis on either aspect. Matter and souls are considered parts or 'powers' of God which are not distinct or separate from Him.
While the Gaudiya Sampradaya worships Sri Radha Govinda in parakiya (paramour) mood, in manjari bhava, the Nimbarka sampradaya worships Radha Krsna in swakiya (wedded) mood, in sakhi bhava. They put forth sambhoga rasa (union), while Sri Caitanya Mahaprabhu emphasized vipralamba rasa (separation).
Brahman is Ramakanta; Purusottama. Radha Krsna is the transcendental form served by the gopis. The qualities of Brahman are described as having dual nature - advaita and dvaita or Nirguna and Saguna - like serpent and coil. The soul is atomic, individual, possessing knowledge and it is dependent on Hari - like the sea and waves or the sun and its rays. Creation is the transformation of Brahman, who is both the efficient and material cause. The cause of bondage is contact with karma resulting from ignorance, which is beginning-less. The process of release is through uninterrupted worship (Bhagavata). The goal is realization of the self, in natural form, no power of creation.