O Partha, one who does not keep turning the wheel set in motion in this way, whose life is sin and whose delight is in the senses, lives in vain here in this world.
Explanation
Krishna is concluding his teaching on the cycle of mutual giving: sacrifice (yajña) sustains the world, and the world sustains us in return. Someone who takes from this cycle but gives nothing back, and lives only for sense pleasure (indriyārāma), is called "of sinful life" (aghāyu) and is said to live in vain. Commentators differ on what the "wheel" asks of us. Some stress ritual duties set out in the Vedas, while others stress selfless action offered for the good of all.