या निशा सर्वभूतानां तस्यां जागर्ति संयमी ।
यस्यां जाग्रति भूतानि सा निशा पश्यतो मुनेः ॥ २.६९ ॥

yā niśā sarva-bhūtānāṁ tasyāṁ jāgarti saṁyamī |
yasyāṁ jāgrati bhūtāni sā niśā paśyato muneḥ || 2.69 ||

Krishna now proceeds to illustrate how the world of the Self and the world of objects differ, and how one devoted to the inner world will irresistibly lose his charm for the outer world. The illustration is quite striking:

What is night to the ordinary people, there does the Yogi Knower remain awake. Where ordinary people remain awake, there indeed the spiritual Knower finds utter darkness.

The world before the senses is the object hemisphere.  It is no doubt colourful.  Attractions and repulsions it evokes are endless.  Nevertheless, it is perishable, changeful to the core, falsifying too. No sense object can be relied upon for any good length of time.  Can this fact be set aside or forgotten?  The question becomes irresistible before the intelligence.  Should not man value his buddhi – its enquiry and guidance?  Or, can he be led only by the senses, eschewing introspection and evaluation altogether?  Human life can become meaningful and will be led to its destined fulfilment only when the buddhi constantly plays its role of evaluation and guidance.

Thus the Knower regards the sphere of objects – the outer world of thrills and excitement – as sheer darkness.  Instead of revealing the true nature of things, it covers up the  truth and forces on us a distorted vision.  The Knower therefore shuns it altogether.  He seeks delight in Knowledge and Knowledge alone.  Knowledge is his supreme resort, enduring wealth, nay the ultimate treasure.  He derives all his joy from Knowledge.  As Angiras tells Saunaka in Mundakopanishad:

“Vedanta-vijnana-suniscitarthah...” (II 3.6)

–He determines the object of human pursuit on the basis of the knowledge revealed in Upanishads, the Vedanta.  Everything else is meaningless for him.  In the light of his wisdom, however extensive and various the world of objects is, it falls short of what he yearns for.  It has no power to elevate man from his perishable fate.  Every day it is the same eating and drinking, seeing and hearing, smelling and tasting – a routine which every other being also does.  The Knower disregards it as hollow and ultimately malignant to the mind !

Whereas the inner world – the world of the Soul, the expanse, beauty and calm which the inward Soul holds and extends – strikes as supremely unique and wonderful for him.  Neither the quest for the Soul nor its discovery, nor again the delight and fulfilment it offers, poses any conflict to the others around.  Nor can there be any conflict from others to him.  Any external pursuit of object, on the other hand, is likely to evoke conflict with others around - competition, quarrel and even fight!

Such an exclusively sovereign inner world, the domain of the Soul, alone is of interest to the knower.  This naturally distances him from the rest of mankind and their widespread craze.  In the same way, the  majority of others are also perhaps likely to remain distant from him, until at last,  by incident or accident, they turn (like Arjuna) thoughtful or disappointed and yearn to seek Sreyas, and in that unyielding quest look to the Knower for help and tuition, finding none others to help or assist them!

The dissimilarity, the mutually opposite character of the Knower and the ordinary mankind, is thus quite evident.  Krishna’s illustration of this  striking difference between the two with ‘Day and Night’  is therefore immensely profound and revealing. The seeker should not fail to ruminate constantly over this and build up his viveka and vairagya.