The senses, they say, are the horses; the objects of the senses are the roads. The Ātman united with the senses and the mind, the wise call the enjoyer.

This verse completes the famous chariot metaphor begun in the previous verse (1.3.3), adding the remaining elements of the analogy.

Indriyāṇi hayān — the senses are the horses. The five senses of perception (jñānendriya: hearing, touch, sight, taste, smell) and the five senses of action (karmendriya: speech, hands, feet, organs of excretion and reproduction) are like horses that pull the chariot. They are powerful, swift, and inclined to follow their own impulses.

Viṣayān gocarān — the sense objects are the roads. Sounds, textures, forms, tastes, and smells are the paths along which the horses run. The word gocara (literally “where the cows go”) suggests the natural grazing field of the senses.

Ātma-indriya-mano-yuktam — the Ātman united with senses and mind. This conjunction describes the individual being (jīva), the Ātman apparently conditioned by its instruments.

Bhoktā — the enjoyer, the experiencer. The wise (manīṣiṇaḥ) call the Ātman this when it is associated with the body-mind complex. In its pure state, the Ātman is not an enjoyer of anything; experience arises only from its association with instruments.

The metaphor has direct practical implications for yoga: if the horses (senses) are not well-tamed, if the reins (mind) are loose, if the charioteer (buddhi) is asleep — the journey ends in disaster. The control of the senses (indriya-nigraha) that will develop in later haṭha yoga has its philosophical foundation here.