Krishna offers one of the Gita's most remembered images. Whoever offers all actions to Brahman and works without attachment — that person remains untouched by sin, just as a lotus leaf remains untouched by water.
Children know that the lotus grows in mud, lives in water — yet not a single drop stays on its surface. This is the yogi's nature. They live in the world, they work in the world, but the world does not stick to them.