MEANS  TO ATTAIN THAT SUPREME ABODE

purushaha sa parah paartha bhaktya labhyastwananyayaa
    yasyaanthahsthaani bhootaani yena sarvamidam tatam // 8.22 //

That Supreme Purusha, in whom  all beings abide and by whom the entire universe is pervaded, can be attained,  O Partha, by undistracted devotion directed to Him alone.

The technique by which the  Unmanifest, the Imperishable - the Supreme Purusha is attainable is explained. Single  pointed devotion with the total detachment from the world of body, mind and  intellect is the means to achieve the Supreme Purusha. The detachment from the  false is achieved by the growing attachment with the Real. Total Identification  of oneself with the experience of the Self or the realization that nothing  exists except the Lord, is undistracted devotion.

In whom all beings abide - All  the beings (which are the effects) dwell within the Purusha, the Supreme Person  (which is the cause) because every effect rests in its cause just as all mud  pots (which are the effects) exist in the mud (which is the cause). The mud  pervades all mud-pots irrespective of their size and shape. The essential  nature of the mud-pot is nothing but the mud from which it is born. So also all  beings and the world rest within their cause, the Purusha and hence the whole  world is pervaded by the Purusha.

But for the cotton the beauty of  the design woven in the cloth made out of that cotton cannot get projected.  When Pure Awareness acts through vasanas It becomes the multiple worlds of  names and forms. Therefore when one realizes the Self, he understands the very  core out of which the world of multiplicity called Samsar has arisen.

Brahman is called Purusha (Person)  because It dwells in every body (pura) or It is full (poornam).

THE TWO PATHS

yatra kale twanaavrittim aavrittim chaiva yoginah
    prayaataa yaanti tam kaalam vakshyaami bharatarshabha // 8.23 //
    Now I will tell you, O Chief  of Bharatas, the time in which the yogis depart never to return and also the  time in which they depart to return.

Sri Krishna now tells about the  routes taken by the seekers to reach the two different destinations viz. the  one from which there is a return and the other from which there is no return. The  former is a Divine Mission seeking the Imperishable by ending the ego and  re-discovering ones own Real Nature as none other than the Eternal  Consciousness, the Changeless Substratum of the whole universe. The latter path  is the life of satisfying the ego by gaining the experiences of joy among sense  objects each of which ultimately brings forth sorrow.

These two worlds differ from each  other since the one leads to a return again and again to a finite embodiment  for living a life of limitations and the other assures a goal, having reached  which, there is no return and where one enjoys Absolute Bliss.

If there are two different  destinations there will be two separate routes guiding the respective types of  seekers to reach their correct places. The Lord promises Arjuna that He will  explain both the `Path of return' and the `Path of no return'. Here, the word `Kale' means the time of departure as well as the path pursued by different types of  seekers at the end of their present manifestations.

agnirjyotirahah shuklah shanmaasaa uttaraayanam
    tatra prayaataa gacchanti brahma brahmavido janaah // 8.24 //

Fire, flame, day-time, the  bright fortnight, the six months of the northern passage of the sun, departing  when the men who know Brahman go to Brahman.

dhoomo raatristathaa krishnah shanmaasaa dakshinaayanam
    tatra chaandramasam jyotir yogee praapya nivartate // 8.25 //

Attaining to the lunar light  by smoke, night-time, the dark fortnight, or the six months of the southern  passage of the sun, the yogi returns.

The verses 24 and 25 have been  commented upon differently by different commentators. Fire, flame, day-time, the  bright fortnight, the six months of the northern passage of the sun - all these  indicate the path of the Gods presided over by the sun while the path of the  ancestors is described in the verse 25 which is presided over by the moon. The  path of Gods is the path of illumination that leads to liberation from where  there is no return for the departed souls. On the other hand the path of  ancestors is the path of darkness which leads to rebirth.

These two verses indicate that a  seeker trying to raise himself above the various matter-envelopments and his  identifications with them, can reach the higher spiritual realms of the  Ultimate in his life time itself. But in case he happens to run after pleasure  and sensuality, he comes back again to the field of action here wherein he can  again make or unmake himself.
    shuklakrishne gatee hyete jagatah shaashwate mate
    ekayaa yaatyanaavrittim anyayaavartate punah // 8.26 //

Truly these bright and dark  paths of the world are considered eternal; one leads to non-return, and the  other one returns.

Both these paths are eternal  because worldly existence of finitude and change or Samsara is eternal. But as  per Vedanta the Samsara can be ended for the individual through sincere  meditation.

Life is a conflict between light  and darkness. The former makes for release and the latter for rebirth. The Lord  here uses the ancient belief to illustrate the great spiritual truth that those  who are lost in the darkness of ignorance go by the path of the ancestors and  are subject to rebirth and those who live in the day of illumination and walk  on the path of knowledge obtain release from rebirth. This attainment of  liberation through Self-Knowledge, while living in a physical body, is the goal  of human life. The other courses, paths etc. are described in order to spur men  to strive for Self-Knowledge and for attainment of liberation here on earth.

naite sruti paartha jaanan yogee muhyati kashchana
    tasmaat sarveshu kaaleshu yogayukto bhavaarjuna //8.27 //

O son of Partha, no Yogi is  deluded after knowing these paths. Therefore Arjuna, at all times you be  steadfast in Yoga.

Knowing that one of the paths  leads to Samsara and the other to Moksha, the Yogi takes up the one leading to  illumination and rejects the other. Here Yogi is the one who has withdrawn  himself from his false-identifications and entered into contemplation of the  Self with single-pointed mind.

In short, this entire Chapter is Krishna’s  advice to Arjuna that he should, even while acting in this world, strive constantly  to be the one living in the awareness of the Divine, through selfless  identification with the Eternal, the Imperishable Purusha. The guiding  principle is that whatever work one undertakes, he should not lose sight of the  Eternal.