Krishna details the precise methodology of the active Yogi. He lists the instruments of action: the physical body (kāyena), the mind (manasā), the intellect (buddhyā), and even the raw senses (kevalair indriyair api). The Yogis perform their actions (yoginaḥ karma kurvanti) using all of these instruments, but they do so having completely abandoned attachment (saṅgaṃ tyaktvā). Why do they act? Krishna gives the singular, exclusive reason: strictly for the purification of the self (ātma-śuddhaye).