A class on Srimad Bhagavatam 1.2.9 given by His Divine Grace A.C. Bhaktivedanta Swami Prabhupada on October 20, 1972 in Vrindavan, India.
A transcript of the class can be found here: https://goo.gl/owhtNK.
Srimad Bhagavatam 1.2.9
dharmasya hy āpavargyasya
nārtho ’rthāyopakalpate
nārthasya dharmaikāntasya
kāmo lābhāya hi smṛtaḥ
All occupational engagements are certainly meant for ultimate liberation. They should never be performed for material gain. Furthermore, according to sages, one who is engaged in the ultimate occupational service should never use material gain to cultivate sense gratification.