CHAPTER THREE: SADHANA ADHYAYA
Section 4: Agnindhanadyadhikaranam: Topic 5 (Sutra 25)

Sannyasins need not observe ritualistic acts, as Brahma Vidya or knowledge serves their purpose.
Ata eva chagnindhanadyanapeksha III.4.25 (450)
And, therefore, there is no necessity of the lighting of the fire and so on.
Ata eva: therefore, only, for this reason only; Cha: and, also; Agni: fire; Indhanadi: fire-wood, and so on, kindling fire and performing sacrifices, etc.; Anapeksha: no need, has not to be depended upon. (Agni-indhanadi-anapeksha: no necessity of lighting fires, etc.)
This Sutra states that the seeker of Brahman may dispense with sacrificial rites.
Brahma Vidya has no need for fire, fire-wood, etc. It is by itself the cause of emancipation.
In Sutra III.4.1 it was stated that the knowledge of Brahman results in the attainment of the highest Purushartha or goal of life. The expression "Ata Eva" (for this reason alone) must be viewed as taking up Sutra III.4.1 because thus a satisfactory sense is established. For this very same reason, i.e., because knowledge serves the purpose of Sannyasins, the lighting of the sacrificial fire and similar works which are enjoined on the householders, etc., need not be observed by them.
Thus the Sutrakara sums up the result of this first Adhikarana, intending to make some further remarks.
As a Sannyasin, devoted to the meditation on Brahman is stated in Sruti to attain immortality and not any of the rewards arising from sacrificial rites, he is not required to have recourse to sacrificial works to be performed with fire, fire-wood and so on. Chhandogya Upanishad declares, "Brahmasamstho'amritatvameti – One devoted to Brahman attains Immortality" (Chh. Up. II.23.1).
The theory or doctrine that knowledge and work must be combined in order to produce Mukti or salvation is hereby set aside. Brahma Vidya or Knowledge of Brahman is sufficient for that purpose.