|Chapter 3: Karma-yoga|
saha-yajnah prajah srishtva
esha vo 'stv ishta-kama-dhuk
In the beginning of creation, the Lord of all creatures sent forth generations of men and demigods, along with sacrifices for Vishnu, and blessed them by saying, "Be thou happy by this yajna [sacrifice] because its performance will bestow upon you everything desirable for living happily and achieving liberation."
Krishna begins with the lowest rung of the yoga ladder – namely karma-kanda. The karma-kanda is meant for people who still desire sense gratification. For such people the Lord has created this material world that gives them the ability to enjoy. He also creates yajna or sacrifice that allows them to enjoy religiously. In doing so they satisfy their inherent needs to enjoy and by submitting to the authority of the scriptures they develop piety, faith and thus gradual purification to rise to the next level of the yoga ladder. The word yajna invokes images of roaring fires, oblations, mantras etc. While this is indeed one form of yajnas – it is not the only form. Especially in the age of Kali, where there is lack of ingredients, qualified priests and purity – it is impossible to perform this form of fire-yajnas and derive benefit for them. Yajna means sacrifice – and one can make a sacrifice by words, actions and mind. In the present age, the sankirtana-yajna is recommended – sacrificing the words in remembering and glorifying the Lord. Srila Prabhupada while commenting on this verse explains this higher purpose, "By performance of yajna, the conditioned souls gradually become Krishna conscious and become godly in all respects. In the Age of Kali, the sankirtana-yajna (the chanting of the names of God) is recommended by the Vedic scriptures, and this transcendental system was introduced by Lord Caitanya for the deliverance of all men in this age."
Please read the Sanskrit Verse and the Prabhupada's Purport.