Everyone believes that Shri Krishan Ji gave the knowledge of Shrimad Bhagavad Gita.
The reality however is something else but even if we continue on this premise that Shri Krishan Ji gave the knowledge of Gita,
then also there are numerous verses to consider from Shrimad Bhagavad Gita itself which prove some other Supreme God which Shri Krishan Ji refers to.
In Gita Adhyay 18, 61-62, 64, 66; Adhyay 15 Shlok 4, 16-17; Adhyay 13 Shlok 12 to 17, 22 to 24, 27-28, 30-31, 34; Adhyay 5 Shlok 6 to 10, 13 to 21 and 24-25-26; Adhyay 6 Shlok 7, 19, 20, 25,
26-27; Adhyay 4 Shlok 31-32; Adhyay 8 Shlok 3, 8 to 10, 17 to 22; Adhyay 7 Shlok 19 to 29; Adhyay 14 Shlok 19 etc-etc Shloks the speaker of Gita has mentioned about some other God than himself.
Firstly, the Speaker of Gita ji in Adhyay 18 Shlok 62 is asking Arjun to go in to the refuge of some other Supreme God to achieve Supreme Peace, happiness and Eternal Place.
Secondly, Shri Krishna says that his salvation is of inferior quality in Gita Adhyay 7 Shlok 18.
People ask this Question: - You have written incorrect meaning in the translation of Gita Adhyay 7 Shlok 18.
You have written the meaning of “Anuttamaam” as “Ashreshth” / “Bad / Inferior”; whereas in compound, the meaning of ‘Anuttam’ is ‘Ati Uttam’ / ‘very good’.
Compared to whom there is no one better, regarding him/it in compound the meaning of ‘Anuttam’ is ‘Ati Uttam’.
Answer: - The giver of the knowledge of Gita is telling about his worship in Gita Adhyay 7 Shlok 16 to 18.
If in Gita Adhyay 7 Shlok 18 he is describing his worship as “Anuttam”,
whose meaning according to your compound is this that there is no better salvation than the salvation of the giver of the knowledge of Gita then there should be no other God superior to him.
Then why in Gita Adhyay 18 Shlok 62 and Adhyay 15 Shlok 4, the speaker of Gita is himself telling Arjun to go in the refuge of some other God?
He further says that only by the grace of "that God", supreme peace and the eternal place, the ever-lasting place of salvation i.e. Satlok will be attained.
About himself also, he has said that I am also in His (that God's) refuge only.
One should worship that Supreme/Complete God alone, and has stated that one should attain the supreme state (Satlok) of that Supreme God.
Having gone where, worshippers never return to this world i.e. their birth and death ends forever.
Gita Adhyay 7 Shlok 19:
In this mantra, Brahm (Kaal) is saying that even my sadhna is done by only a few; only a fortunate person does it after many births; otherwise,
one’s intellect does not rise above the bhakti of the lower gods, Shri Brahma Ji, Shri Vishnu Ji, Shri Shiv Ji and other gods, ghosts and pitras (spirits of deceased ancestors).
But it is very difficult to find a saint who tells that only the Supreme God is worthy of being worshipped.
He is the Creator of the whole universe; He only fosters and protects everyone, is the Almighty. In reality, He only is ‘Vasudev’. The meaning of Vasudev is ‘the Master of all’.
In Gita Adhyay 7 Shlok 29 the speaker of Gita says
"Those who know my entire adhyatm/religious knowledge and all actions, those men strive to get rid of old age and death and they know that Brahm (tat brahm)."
Here the Speaker of Gita ji is referring to some other God. Therefore Arjun asks the speaker of Gita ji in Adhyay 8 Shlok 1about "that Brahm" (tat brahm).
Arjun questions Krishna ji that "who is that brahm you are talking about?"
Gita Adhyay 8 Shlok 1
"Oh Purushottam! What is that Brahm? What is Adhyatm? What is Karm? What is called by the name Adhibhoot, and who is said to be Adhidev?"
The speaker of Gita ji then answers in Adhyay 8 Shlok 3 and says it is "Param Aksharam Brahm".
The Speaker of Gita ji is referring to some other God as Param Akshar Brahm here.
In Gita Adhyay 8 Shlok 6, the speaker of Gita has said that it is a rule that in the final moments, while remembering whichever God (Brahm, ParBrahm, Purna Brahm), a devotee leaves his body,
he goes to him (that God) only.
It is this same God "Param Akshar Brahm" (Supreme God), that the Speaker of Gita ji is asking Arjun to go in to refuge of in Adhyay 18 Shlok 62 and then again in shlok 66.
Gita Adhyay 18 Shlok 62
Oh Bharat! You, in every respect, go in the refuge of only that Supreme God hidden in the darkness of ignorance.
By the grace of that Supreme God, you will attain the supreme peace and the everlasting – Sat lok (place-dhaam).
Gita Adhyay 18 Shlok 66
Abandoning all my religious practices in me, you go in the refuge of that one Purna Parmatma (Supreme God). I will liberate you from all the sins; you do not grieve.
Read Gist of Bhagavad Gita Adhyay 18