Know the Self as the owner of the chariot, the body as the chariot itself; know the intellect as the charioteer, and the mind as the reins.

The famous chariot metaphor: the human being as vehicle driven by the Self.

Ātmānaṃ rathinam — the Self as owner of the chariot. The passenger, the possessor, the traveler.

Śarīraṃ ratham — the body as the chariot. The physical vehicle, the structure that transports.

Buddhiṃ sārathim — the intellect as charioteer. The capacity of discrimination that guides.

Manaḥ pragraham — the mind as the reins. The instrument that connects charioteer and horses, that directs attention.

The image is clear: the Self (ātman) is the passenger who, through the body (śarīra) guided by the intellect (buddhi) and the mind (manas), experiences the world.

Yoga works in strengthening the charioteer (buddhi) so that he properly controls the reins (manas) and thus the journey is toward liberation.