Bhagavad Gita · Chapter 17: The Three Kinds of Faith

Bhagavad Gita 17.12

abhisaṃdhāya tu phalaṃ dambhārthamapi caiva yat | ijyate bharataśreṣṭha taṃ yajñaṃ viddhi rājasam ||

But a sacrifice that is offered with its reward in view, or simply for show, best of the Bharatas: know that sacrifice to be of passion.

Modern context

A rajasic offering is made with an eye on the reward, or simply to be seen. Charity galas, public displays of piety, generosity that makes sure everyone notices: these are rajasic. They may still do good, but they are mixed with self-interest. The verse is not condemning them so much as naming what they are, so that one can aim higher.