how can we trust such when the knowledge around then was hardly above caveman level?
The idea you believe in Caveman theory in the last ten thousand years is silly sorry; we had advanced civilizations before the flood, that built pyramids all over the world.
We then had entheogen assisted cultures like the Land of Mu, Bon (Tibetan), Egyptian, Greek, etc which were highly educated, and now in this modern times, people are dumbed down by chemicals in their diets on purpose.
Moses sets up a Curse (Deuteronomy 28), where it says the people will eventually not listen to the things of the Source of reality (God); so they will go against murdering their own Messiah (Zechariah 11, Isaiah 52:10-14 - Isaiah 53:1-11), and then choose their own Leaders.
Then a Holy Fire will come (Deuteronomy 29:19-27) where Yeshua sets the Snare, as people don't listen properly (Deuteronomy 32:15-22).
The idea we see that the Children of Israel suffered for the last two thousand years what Moses stated, means the next bit is inevitable, and it is only a lack of study that leads people not to be aware of how concise it all is.
Rabbinic Judaism (Zionism) according to the Curse is exactly opposite to the truth (Deuteronomy 31:24-29, Deuteronomy 28:28-29, Zechariah 12:4); so the world is currently upside down on purpose, before they try to start WW3.
If Rabbinic Judaism accepted Messianic prophecy on Religious Forums, there are other potentialities.
The worst bit of what you just stated, is the
Gospel of John is made up to catch out the hypocrites, and Yeshua didn't actually say "Love One Another"...
Yeshua taught we're down near Hell in Judaism (Matthew 23:15, Matthew 23:33), and to love Source first with both eyes (Matthew 6:22-24); then to unconditionally love people (Matthew 22:37-40), as they are evil since we're down near Hell (Matthew 7:11), so matter corrupts us (Matthew 6:19-21).
Try actually questioning independently, before accusing everyone religious of being bias.
In my opinion.