The vānaprastha stage: practicing tapas, dwelling permanently (nityaṃ), maintaining the sacred fire (sāgnihotra), and remaining concentrated (samāhita). Then, having established the fires within oneself (ātmanyagnīn samāropya), one renounces (sannyaset) according to prescription. The internalization of the sacrificial fires — from external ritual to inner absorption — is a pivotal moment in the spiritual journey and a key concept in yogic philosophy.