Gita Explained
कृष्ण कहते हैं4.3

स एवायं मया तेऽद्य योगः प्रोक्तः पुरातनः।भक्तोऽसि मे सखा चेति रहस्यं ह्येतदुत्तमम्॥

sa evāyaṃ mayā te ’dya yogaḥ proktaḥ purātanaḥbhakto ’si me sakhā ceti rahasyaṃ hyetad uttamam

शब्दार्थ
saḥthatevacertainlyayamthismayāby meteunto youadyatodayyogaḥthe science of Yogproktaḥrevealpurātanaḥancientbhaktaḥdevoteeasiyou arememysakhāfriendcaanditithereforerahasyamsecrethicertainlyetatthisuttamamsupreme

व्याख्या अभी अंग्रेज़ी में उपलब्ध है। हिन्दी व्याख्या एक-एक अध्याय करके जोड़ी जा रही है।

श्लोक कहता है

That same ancient practice is what I have told you today. You are devoted to me, and you are my friend. That is why — this is the best of secrets.

सरल शब्दों में

Krishna gives the reason Arjuna is hearing this, and it is not the reason you would expect.

Not because Arjuna is worthy. Not because he asked well. Because bhakto 'si me sakhā ca — you are devoted to me, and you are my friend.

The qualification is a relationship.

आपने इसे कहाँ महसूस किया है

Someone tells you the thing they have never told anyone. Not because you are wise. Because it is you, and you were there, and they have known you twenty years.

और गहराई में

This is the first time in the Gita that bhakta appears, and it arrives almost casually, inside a reason rather than a teaching.

The order of the two words repays attention. Bhaktaḥ — devotee — and then sakhā — friend. Not one or the other. Both at once, which is a combination that ought to be unstable and is presented as ordinary.

That pairing is the Gita's particular flavour. The relationship between these two is not the awe of a worshipper before a deity. They are cousins who have known each other for years and one of them is driving the other's chariot.

Rahasyam uttamam — the highest secret. The word rahasya will come back at the very end, at 18.64, where Krishna calls what he is about to say the most secret of all.

So the chapter marks itself, at its opening, as the beginning of something more intimate than what came before. Chapters 1 to 3 were argument. From here the register changes.