In this page, I would like to show (through some reasoning/logic) that some of the slokas shouldn't belong to Bhagavadgita. Many of the times the reasoning is based on the fact it is Bahavadgita (a song of GOD). Here, I assumed that the meaning of GOD as a person who knows everything. If you don't agree with this meaning of GOD, then there is no need to read the rest of this page.
Parithranaya Sadhunam (Chapter=4, Sloka=8 => 4:8)
Today (22-Oct-2015) morning, suddenly, I got convinced that this sloka should not belong to Gita?
Paritraanaaya sadhoonaam vinaasayacha dushkruthaam
dharma samsthaapanaarthaaya sambhavaami yuge yuge ...
My reasoning was like this ...
1) At a simple logical level if you think ::--
Clearly, from the sloka ... all he want to do is to establish dharma (probably in the society). If it is his main aim and if he thinks that he has the ability to do so ... then (for GOD sake) why can't he do it right from the beginning and establish a peaceful society
2) At a little deeper level (when you read and understood earlier chapters of Gita (2 and 3)) ::--
It is mandatory for a person seeking liberation that he/she should attain equanimity (dvandva atheetha). Being YOGACHARYA, Krishna is also expected to have equanimity. But, through this Sloka it is very clear that he is discriminating people (some are sadhoos and some are dushkruthas). For those who can't understand equanimity: Equanimity comes very naturally once you know more and more regarding nature, evolution etc. Ask any renowned wild-life photographer/cinematographer, whether he stopped any lion eating a deer or a cow. You will soon realize that for him neither the deer is Sadhu nor the Lion is Dhuskrutha! They are just animals struggling for their life.
Both of these arguments clearly suggest that this sloka has been written by a "Human being" (may be Vyasa) with good knowledge. But, if you still believe that it is said by Krishna then the logic says that Krishna is not a being with complete knowledge.
Nakshatranaam Aham Sasi (10:21)
Though the whole 10th chapter looks to me as if it is incorporated at a latter stage (I feel that its not written by Vyasa), this particular Sloka gives me a clear clue that it is certainly written by a "Human being" (or surely not by a intelligent being who knows everything).
adityanam aham visnur jyotisam ravir amsuman
maricir marutam asmi naksatranam aham sasi
The writer of this sloka clearly want to say that "Among the Adityas HE is the Vishnu, among radiating objects HE is Sun (literally he said he is a part of Sun), Marici among Maruts, and among the stars HE is the moon". Clearly, HE is judging what is the best among certain things and HE is saying that HE is that best thing among the others. Thus, this sloka should not belong to Gita because
1) At a simple logical level if you think ::--
Moon is a satellite and the writer is saying that Moon is the best among stars. Common man ... look up!
2) At a little deeper level (when you read and understood earlier chapters of Gita (2 and 3)) ::--
You are judging planets, objects etc. and you are preaching us equanimity!
Both of these arguments clearly suggest that this sloka has been written by a "Human being" with good knowledge at his time. But, if you still believe that it is said by Krishna then the logic says that Krishna is not a being with complete knowledge.