I know that Robespierre was heavily influenced in his political thought by Rousseau, and one of the influences was Rousseau's notion of national virtue. Robespierre stated that the Republic was founded on two principles, "virtue and its emanation, terror." Are there any works of Rousseau which illustrate a belief in such a relation that may have persuaded Robespierre to think along such lines? Thanks for any and all help.
That's not exactly what Robespierre said.
The full quote is
If virtue be the spring of a popular government in times of peace, the spring of that government during a revolution is virtue combined with terror: virtue, without which terror is destructive; terror, without which virtue is impotent. Terror is only justice prompt, severe and inflexible; it is then an emanation of virtue; it is less a distinct principle than a natural consequence of the general principle of democracy, applied to the most pressing wants of the country.
The actual ideal here is the government founded on virtue. "Revolution" here means a sort of state of emergency, when democracy is threatened. That threat, the counterrevolution, needed to be fought to preserve the republic, the revolutionaries needed a way to explain themselves ideologically, and that's basically what this speech is.
The political climate didn't look kindly on people who changed their minds on big issues, which meant Robespierre couldn't just go up and say "hey, remember when I said free press was great? Well it's not, we need to kill some journalists now", so if there were some journalists who needed to get got, he had to find a way to explain why these changes to his (and the government's) politics weren't actually changes at all.
The new laws also needed to not be a threat to the ideals of the Revolution, or they risked making new enemies in an attempt to defeat the old ones.
so in summary, no, it's not Rousseau. It's a response to the position the government Robespierre was a part of found itself in in February 1794.