If the father and the mother do not undertake the process of spiritual family planning and simply beget children out of passion only, their children are called dvija-bandhus. These dvija-bandhus are certainly not as intelligent as the children of the regular twice-born families. The dvija-bandhus are classified with the sudras and the woman class, who are by nature less intelligent. The sudras and the woman class do not have to undergo any samskara save and except the ceremony of marriage.

The less intelligent classes of men, namely women, sudras and unqualified sons of the higher castes, are devoid of necessary qualifications to understand the purpose of the transcendental Vedas. For them the Mahabharata was prepared. The purpose of the Mahabharata is to administer the purpose of the Vedas, and therefore within this Mahabharata the summary Veda of Bhagavad-gita is placed. The less intelligent are more interested in stories than in philosophy, and therefore the philosophy of the Vedas in the form of the Bhagavad-gita is spoken by the Lord Sri Krsna. Vyasadeva and Lord Krsna are both on the transcendental plane, and therefore they collaborated in doing good to the fallen souls of this age. The Bhagavad-gita is the essence of all Vedic knowledge. It is the first book of spiritual values, as the Upanisads are. The Vedanta philosophy is the subject matter for study by the spiritual graduates. Only the post-graduate spiritual student can enter into the spiritual or devotional service of the Lord. It is a great science, and the great professor is the Lord Himself in the form of Lord Sri Caitanya Mahaprabhu. And persons who are empowered by Him can initiate others in the transcendental loving service of the Lord.