…a paid servant is also engaged in satisfying the master very nicely, very faithfully, but there is no bhakti. Why? Because he is after the money the master pays. He does not serve the master, but he serves the money. He is thinking always that "I am getting so much money from this person. If I don't satisfy him, then I may be dismissed. So I will have no money." But here it is said bhaktya. Bhaktya means without any material concern.

Srila Prabhupada, lecture, 12 Sep 1971