Anvadhana Sangraha -

Within this, there are multiple Anvādhānas :

The primary purpose of Anvadhana is to ensure that the fires, which represent the presence of the deities on earth, do not extinguish. The sacrificer (Yajamana) adds Samidha (sacred sticks) to the altars while reciting specific mantras. This act is not merely maintenance; it is a symbolic rekindling of the seeker's inner resolve and a formal invitation to the Agni to act as the messenger (Hotra) between the human and divine realms. During Anvadhana, the Yajamana often observes a Vrata (vow), which includes fasting or consuming only specific foods to purify the body and mind. anvadhana sangraha