Verse 17.12
अभिसंधाय तु फलं दम्भार्थमपि चैव यत् । इज्यते भरतश्रेष्ठ तं यज्ञं विद्धि राजसम् ॥ १७.१२ ॥
परन्तु हे अर्जुन ! केवल दम्भाचरण के लिये अथवा फल को भी दृष्टि में रखकर जो यज्ञ किया जाता है, उस यज्ञ को तू राजस जान|
However, O Bharata, a sacrifice that is done purely with the intention of receiving some reward, or done for the sake of display, is known as a Rajas sacrifice, which is an impure sacrifice.