Whatever is done without faith—whether it be sacrifice, charity, or austerity—is considered "Asat" (unreal) and is of no benefit here or hereafter.
Krishna concludes by cautioning against faithless actions. Sacrifices, penances, and charity devoid of sincerity are ultimately futile, reinforcing the core message of the Gita—that true spirituality is about intention and purity, not mere outward ritual.