Some offer the senses, such as hearing, into the fires of self-restraint. Others offer sound and the other objects of the senses into the fires of the senses themselves.
Explanation
Krishna is continuing his list of different kinds of sacrifice (yajña), here describing inner disciplines instead of ritual fire offerings. In the first, a person restrains the senses (saṃyama) so that they stop reaching outward. In the second, the person lets sense objects like sound enter the senses, but treats this as an offering and does not respond with craving or aversion. Commentators differ on how the two relate, with some reading them as withdrawal versus mindful, non-attached engagement, but all take both as forms of self-discipline.