If a person wants to return home, back to Godhead, or wants to become a pure devotee (akāma), or wants some material prosperity (sakāma or sarva-kāma), or wants to merge into the existence of the Supreme Brahman effulgence (mokṣa-kāma), he is recommended to take to the path of devotional service and hear and chant of Lord Viṣṇu or of His devotee. This is the sum and substance of all Vedic literatures.