chittvainam samsayam yogam
(Text 42, Ch 4, Transcendental Knowledge)
Meaning: Therefore the doubts which have arisen in your heart out of ignorance should be slashed by the weapon of knowledge. Armed with yoga, O Bharata, stand and fight.
*** Yoga system is eternal activities performed by living entity. This yoga has two divisions of sacrificial actions: one is called sacrifice of one’s material possessions, and the other is called knowledge of self, which is pure spiritual activity.If sacrifice of one’s material possessions is not dovetailed for spiritual realization, then such sacrifice becomes material. But one who performs such sacrifices with a spiritual objective, or in devotional service, makes a perfect sacrifice.