dharanasu cha yogyata manasah ||53||
धारणासु च योग्यता मनसः ॥५३॥
dhāraṇāsu ca yogyatā manasaḥ ॥53॥
And the mind develops the capacity for harmony with thoughts (dharana). ||53||
dhāraṇāsu = (loc. pl. f.) for dharana; concentration; harmony with thoughts; harmony in the mental body; the sixth of the eight steps.
ca = (conj.) and
yogyatāḥ = (acc. pl. f./nom. pl.) fitness; preparedness; qualification; capability
manasaḥ = (g. sg. n./abl. sg. n./acc. pl. m./nom. pl. m./g. sg. m./abl. sg. m. from manas) mind
The sentence above actually occurs earlier, since the ashtanga yoga pratyāhāra technique that follows here is described one sentence later.
Dhāraṇā means concentration. The next step is a natural outgrowth of the previous ones. The harmony that was previously attained with the physical body, energy and emotion now becomes the goal for gaining control over one’s thoughts.
To experience how difficult this is to achieve, do the following brief exercise: While sitting in a comfortable position for a few minutes with your eyes closed, try not to think of a blue elephant with bells around its neck. You will probably find, as do most people, that this is an impossible task, i.e. you will inevitably think about the elephant.
According to the aṣṭāṅga yoga tradition, the key to dhāraṇā lies in the āasana-vinyāsa system. The transition to this step occurs all by itself, thus allowing you to increasingly focus your attention on your practice, which will in turn be imbued with increasing awareness.
Here too, aṣṭāṅga yoga offers a number of other techniques that can be practiced in addition to the āsana-vinyāsa system.