The Vedanta Sutras of Badarayana, Commentary by Sankara (SBE38), tr. by George Thibaut  at sacred-texts.com
16. But the Agnihotra and the like (tend) towards the same effect; scripture showing this.
The reasoning as to evil deeds has been extended to the
non-clinging and destruction of good deeds also. Against a notion which now might present itself, viz. that this extension comprehends all good works alike, the Sûtrakâra remarks, 'But the Agnihotra and so on.'--The word 'but' is meant to set that notion aside. Works of permanent obligation enjoined by the Veda, such as the Agnihotra, tend 'towards the same effect,' i e. have the same effect as knowledge. For this is declared by texts such as the following one, 'Brâhmanas seek to know him by the study of the Veda, by sacrifices, by gifts' (Bri. Up. IV, 4, 22).--But, an objection is raised, as knowledge and works have different effects, it is impossible that they should have one and the same effect!--It is observed, we reply, that sour milk and poison whose ordinary effects are fever and death have for their effects satisfaction and a flourishing state of the body, if the sour milk is mixed with sugar and the poison taken while certain mantras are recited; in the same way works if joined with knowledge may effect final release.--But final release is something not to be effected at all; how then can you declare it to be the effect of works?--Works, we reply, may subserve final release mediately. For in so far as furthering knowledge, work may be spoken of as an indirect cause of final release. For the same reason the equality of effect spoken of above extends only to works past (at the time when knowledge springs up). Because for him who knows Brahman no future Agnihotras and the like are possible, since the attainment of the Self of Brahman--which Brahman is not subject to injunction--lies outside the sphere of sacred precept. In those meditations, on the other hand, which refer to the qualified Brahman, the Self does not cease to be an agent, and consequently future Agnihotras and the like are not excluded. Such works also--because they have no other effect if undertaken without a view to reward--may be brought into connexion with knowledge.
To what works then, it may be asked, does the statement refer made above about the non-clinging and the destruction, and to what works the following statement made in some Sâkhâ about the application of works,' His sons enter upon
his inheritance, his friends on his good works, his enemies upon his evil works?'--To this question the next Sûtra replies.