2. There is no evidence anyone else ever said this, either
The closest you get is MLK.
See https://www.monticello.org/research-education/thomas-jeffers...
But MLK also talks about moral obligation and not other forms of obligation.
He was not trying to create a free for all where everyone gets to decide which laws are okay or not, because he (and jefferson) were not complete morons.
>Conversely, one has a moral responsibility to disobey unjust laws. I would agree with St. Augustine that "an unjust law is no law at all."
Considering that his rhetoric was very much based on Christianity, it's clear what standard of "unjust" he was applying.
Considering the diversity of standards of justice within the history of Christianity (which, in just the US, includes—relevant to this topic—MLK, sure, but also the Southern Baptist Convention, founded explicitly in support of slavery), I don't know that having rhetoric grounded in Christian theology tells much of substance about the standard of justice one is appealing to.