How is it to be understood that performing the same actions some people are bound to material existence and others are released from material bondage?  Shree Krishna gives the answer in this verse.  Those who are unattached and unmotivated by material rewards are never bound by karma.  But those craving reward and obsessed with the desire to enjoy material pleasures become entangled in the reactions of work.
The word
yukt
means “united in consciousness with God.”  It can also mean “not wanting any reward other than purification of the heart.”  Persons who are
yukt
relinquish desire for the rewards of their actions, and instead engage in works for the purpose of self-purification.  Therefore, they soon attain divine consciousness and eternal beatitude.
On the other hand,
ayukt
means “not united with God in consciousness.”  It can also denote “desiring mundane rewards not beneficial to the soul.”  Such persons, incited by cravings, lustfully desire the rewards of actions.  The reactions of work performed in this consciousness bind these
ayukt
persons to the
samsara
or the cycle of life and death.