Ahitagni is the initiation of a Brahmin householder who has performed agnyadhana (kindling of the fire through friction) and set up the sacred Vedic fire with the help of his wife. This initiation generally takes place at the time of marriage. The fire enables the householder to perform other fire yajnas.
Three fire-altars are set up. The three fires are – garhapatya agni – the perpetual household fire, which is placed in a round altar; the ahavani agni – the fire for invocation in a square altar; and the dakshinagni – the southern fire in a semi-circular altar. The first one is kept burning day and night. If it is extinguished, it has to be re-kindled by friction again (punaradhana). This agnyadhana is the first fire setting, which enables the householder to perform other yajnas like agnistoma, and atiratra.
Oblations of clarified butter have to be offered at least twice daily. The invoked deities are generally Agni (the fire-God) and Prajapati (progenitor God) and occasionally Surya (the Sun God). If the votary leaves the house, he has to take leave of the sacred fires, and greet them upon his return. In this absence, the wife, pupil or an appointed priest has to tend the fire. Certain rituals have to be followed, varying according to the situational content and textual injunctions. When the householder dies, the fire from the southern altar is used to kindle the funeral pyre.
Fire, as a harbinger of light, was worshiped in ancient society. In Vedic culture, fire was considered to be the intermediary between man and God. As the protector of the sacred fire, ahitagni has an honored place in society, and is the recipient of gifts from others. In order to be worthy of these honors and to continue in his chosen vocation, he has to lead a disciplined life.