1. Devotional service is not mundane

    In our preaching work, we deal with so much property and money and so many books bought and sold, but because these dealings all pertain to the Krsna consciousness movement, they should never be considered material. That one is absorbed in thoughts of such management does not mean that he is outside of Krsna consciousness. If one rigidly observes the regulative principle of chanting sixteen rounds of the maha-mantra every day, his dealings with the material world for the sake of spreading the Krsna consciousness movement are not different from the spiritual cultivation of Krsna consciousness.

    Srila Prabhupada, Srimad-Bhagavatam 5.16.3 purport