The Gita teaches that we can perform the perfection of yogic process by doing our duty in divine consciousness. In Gita, Krishna tells what type of work is worship.
“When work is done in devotion to God in service to humanity that work will liberate us from all the bondage of material creation, but any work that has been done for our own selfish motives, without worship and respect to God, that work will only cause bondage.”
So the Bhagavad Gita is teaching how we can apply spiritual consciousness to our everyday life.
Arjuna and Duryodhana had the same occupation and were doing the same work—fighting—yet Duryodhana is condemned and Arjuna is glorified. Why? Because Arjuna heard Gita and he did his duty selflessly, as a sacrifice, in divine consciousness and in devotion to God for the upliftment of humanity.
Duryodhana did the same thing but with no respect to the word of God. He did it for his own prestige, for his own power, to fulfill his own greed. This is what Gita is teaching—how to change our consciousness. Unless we want that change of consciousness, nothing will take place.