I just gave the verses that he himself said to be best hymns. He didn’t say a specific one. But you have to accept reality. There is two things together. It must be him seeing death. And had heard that there can be a escape. Who knows if he went to ask his royal family Vedas master of what he has seen? I’m not saying he accepted everything in Vedas. But the proof I have found in Pali sutta itself. Savitar is said a little bit different in Pali but that what he mentioned is Savitar. Which I search all 4 Vedas. It took me much time. There is bunch nonsense. But remember he also he met also a sramana who inspired him to go forth. Who knows what they talked. Maybe that sramana gave him a response to his questions of what he has seen , disease, old age, dead. Etc As a response who knows all what he said. But also I didn’t specifically select any specific verses. I wonder why Buddha said that. I downloaded a pdf of all 4 Vedas. In the fourth because maybe Buddha didn’t know about that. Savitar I searched in my iBooks. If you want and can do the same it’s the easiest way to things in a book. Just search Savitar. But Actually now I remember. The pdf I found actually had a cool content director. So I had to just click the hymns. I went to all one by one. It’s mostly in Rig Veda. This is the way I study.
And about Mahabharata my friend it’s just like when Buddha died. When person died thing are not written down immediately. With is different, they started simple teachings to make more suttas with things we cannot be sure he taught. It very difficult.
But I also believed like you. But let me search for you in my notes. I forgot. I do still have the Mahabharata book. What you want to search? First of all don’t believe anything scholars say immediately searching online. Read the book yourself. And search what is the earliest manuscript date. If it’s so important to India why there is not early dated manuscript in temple or something. Even the whole of Rig Veda can not be sure anymore to be from the time of Buddha. There is early parts of the manuscript and later.
An example from Wikipedia
Certain books and chapters in currently surviving Shiva Purana manuscripts were likely composed later, some after the 3rd century CE.[6] The Shiva Purana, like other Puranas in Hindu literature, were routinely edited, recast and revised over the centuries.
Some chapters of currently surviving Shiva Purana manuscripts were likely composed after the 1st century CE.
Notice that even this is a popular tantric text but look what they say.
That war in Mahabharata happened maybe it’s true by tradition. But most of it is latter added. Especially the Gita. Which is just a Hindu version of Buddha. Have you read later Chinese Buddhist scriptures Tripitaka. Buddha is said the a gold and blue skin. While I think in Pali says is like a gold complexion. That’s the from later when Mahayana was in its starting phase. What color is Krishna? Blue right? And does Mahayana when started making stories mention anything about krishna? Which is 2 CE movement. I say this because they mix a lot of Vedas , Hinduism stuff with Buddhism.
Let look one Mahayana text.
Let us for example see The Lankavatara Sutra
According to Asanga Tillekharatna, “it is generally believed that the sutra was compiled during 350-400 CE,”
Exactly when Mahayana is in its “starting to become popular phase”
Four translations of the Laṅkāvatāra Sūtra were made from Sanskrit into the Chinese language between roughly 420 CE and 704, the earliest being attributed in the 5th Century.
Next for me then if Gita was so popular by that time they should mention something.
Let us search in the text.
I will search also in Mahabharata what I told you . But give me time. I can’t find my notes.
But I searching this text there is mention of Vishnu. Like even Hindu scriptures indentify Buddha as Vishnu. As a way to claim is there god. They said that people didn’t notice that Buddha was Vishnu. So who didn’t notice that , got lost.
Now Krishna is also said to a version of Vishnu. So who they started to say this sort tradition first? You have to search a lot it’s endless.
Let go back to the text. There is this
At that time there came to the Blessed One the King of the Nagas, called Krishnapakshaka, who assumed the body of a Brahman and said thus: Gautama, is there not another world?
But there is note.
There is no allusion in the Chinese versions to this dialogue between Krishnapakshaka and the Buddha.
Who is Krishnapakshaka? I don’t know. But I searched and it’s a name use for one of moon phases.
Note also Manjushri Bodhisattva first mention of Mahayana. Like to mention Vishnu also
old believes. But there is some nice teaching here and there. Nice mantras. Etc nice to check it out. It might not be exactly what Buddha learned. But it’s close