I noted a similarity between Plutarch and the New Testament in an earlier post. After some very brief research on JSTOR nothing came up immediately. I did realize two things though.
Authorship of the Gospels
First, I realized the Jesus quote is not only in Matthew but also appears at Luke 9:58. I started speculating once I realized that this has a few implications.
If the similarity between Plutarch and the New Testament is the result of one author influencing the other, then it’s much more plausible that Plutarch influenced the Gospel writers than the other way around. Also, the author of Luke is widely considered to be non-Jewish (though with some Jewish background knowledge), Hellenized, and fairly well-educated. His command of Greek is much greater than the other authors. So, its plausible that if Plutarch influenced the New Testament, he influenced Luke’s author, and Matthew copied Luke. This means either Matthew came later than Luke or the passage in Matthew is an interpolation.
Or, the similarity could just be a coincidence. For example, Gracchus’ speech may have been general common knowledge similar to how some one-liners by American presidents get widely diffused. Perhaps Plutarch and the Gospel author separately used this line. Or perhaps Jesus was also aware of the speech by common knowledge and the attribution to Jesus is original.
It’s possible but unlikely that Jesus himself discovered the quotation while reading. The Gospels note Jesus was literate, and there’s no reason to doubt that he was a reader in the synagogue. Generally, peasants would not be very educated, but Jewish culture would have emphasized the ability to read the Laws of Moses. At any rate, Jesus would have had to be well-versed in the Law to debate publicly and make such a name for himself. So, maybe Jesus got the Tiberius quote on his own. This seems unlikely to me though. If Jesus was literate it would have been in order of likelihood Hebrew first, Aramaic second, and Greek third. Greek would have been the language he would have needed to be able to read to learn about Tiberius Gracchus.
In my inexpert opinion, I think its much more plausible the Lukan author would have found the Tiberius quote while reading Plutarch and attributed a modified form to Jesus, from there Matthew interpolated the quote. Let me emphasize this is just conjecture on my part and not the result of very weighty research. If you disagree please let me know why.
The Roman Law of Common Things
Second, I realized there was something to be said about the Roman law here. More interesting than the similarities between the quotes are the differences.
Tiberius Gracchus: “The beasts of Italy dwelling about each have a den or lying place to go into; but those who on behalf of Italy fight and die have air and light, but a share in nothing else.”
Jesus: “Foxes have dens to live in, and birds have nests, but the Son of Man has no place even to lay his head.”
The quote written by a Roman and attributed to a Roman talks about the poor having a share in the common things of air and light. This is absent from the Jesus quote, and the mention of air and light being common probably reflects an understanding of Roman civil law.
For example, the Louisiana Civil Code (a descendant of the Roman Ius Civile) states: “Common things may not be owned by anyone. They are such as the air and the high seas that may be freely used by everyone conformably with the use for which nature has intended them.”
I think its safe to say that the Plutarch attribution hints at an understanding of air and light being “common things” in the Roman civil law. Plutarch was a magistrate and an archon and would have known some law. The Gospel authors probably didn’t understand this detail and omitted it when they lifted it from Plutarch.