You're surely mistaken. The bible translators often brought in popular sayings and turns of phrase that seemed to fit. If there was a wizard motto with some currency that sounded like an appropriate translation when KJV was written, then I could totally see it being used in the bible, assuming there was any cross-pollination between wizards and christians at the time.
I don't see why the christians using a wizard motto would be particularly blasphemous, let alone maximally so.
Hypothesis: The muggles don't possess much gold. Most of the huge stacks of gold in places like Fort Knox are clever magical replicas, and have been for a very long time. Any wizard can easily see through the ruse, but the muggles are clueless.
How do we have gold that we use as a conductor? Perhaps when a muggle handles fake gold, it gets magically swapped with real gold from a small supply elsewhere. Or else, maybe fake magic gold is a really good conductor.
Indeed, understanding the particular error in reasoning that the person is making is not merely sufficient but necessary for fully understanding a mistaken position. However, if your entire understanding is "because bias somehow" then you don't actually understand.
And you should be careful about accepting the uncharitable explanation preemptively, as it's rather tempting to explain away other people's beliefs and arguments that way.