Whether this was Jefferson's own words or a little fluff thrown in to drive home a point, this is what he did say for sure to John Taylor in 1816:
And I sincerely believe, with you, that banking establishments are more dangerous than standing armies; and that the principle of spending money to be paid by posterity, under the name of funding, is but swindling futurity on a large scale.
So, essentially very similarly to what was claimed he wrote so it's really just a mute point. The fact stands that he was against central banks and likely only in an emergency like a true state of war would he even listen to the central bank grand standers. In modern times, the govt should just say FU to the Federal Reserve and tell them to close up shop cause we ain't paying you shit. Of course, we know the banksters have way more influence than us little people.