This book of Asvalayana, the pupil of Saunaka, pertains to the Vedic Samskaras that are obligatory for man's purification. The elaborate ritual and the manner it is performed indicate the extent to which the life of a Vedic Aryan was involved in ceremonial acts.
The book is arranged into four chapters.
Ch. I consists of 24 sections. It enjoins rites obligatory for the house-holder, the period and tenure of rites such as Initiation, Tonsure, Marriage etc. it elaborates on the establishment of domestic fire, on the offering of oblation son the new and full moon days, on the ritual of animal and Caitya sacrifices. It dwells upon securing the conception of a male child or preventing disturbances likely to endanger the embryo. It deals with the ceremonies of parting the hair, the birth of a child, his nomenclature, his first partaking of the solid food or the Tonsure of his head.
Ch. II is arranged into 10 sections and is primarily concerned with the rites of the full moon day in the months of Sravana, Asvayuj, Margasirsa and the Astaka rites on the eighth days of the four dark fortnights of Hemanta and Sisira seasons. It describes the anvastakya ceremony following the astakas. The ceremony of mounting a chariot or building a house.
Ch. III is divided into 12 sections. It deals with miscellaneous topics, such as the fire sacrifices, the recitation of Vedic texts, satiating the deities and sages, the rite by which the annual course of study opens and the ceremony of attaining to one's desires.
Ch. IV contains 9 sections and deals with the funereal rites of the deceased person.