That is why doctrine and tradition matter.
regarding tradition, Jesus didn’t think too highly of untested tradition:
(Mark 7:8) For you ignore God’s law and substitute your own tradition.”
(Mark 7:9) Then He said, “You skillfully sidestep God’s law in order to hold on to your own tradition.
(Mark 7:13) And so you cancel the word of God in order to hand down your own tradition. And this is only one example among many others.”
Note Jesus did not say all traditions are bad, just to test them.
Personally, I find the old doctrines well tested.
YESHUA is referring to the Talmud, and the oral law, I think, it had already been partly developed.