The search for so called Ur-texts - of which the Ten Commandments were part - was very real, not just in the 19th century. There are various examples from the early modern times too and it is very much connected to the Renaissance tradition.
The Renaissance - the "Rebirth" - for contemporaries meant a return to the truths of the ancients. And this was a very real notion. The closer to the creation of the universe by God, the purer the knowledge, as they saw a corruption and obscuring of that pure knowledge through the centuries. The ancients in the remotest antiquity had had the most pure knowledge and had been closest to God's plan and creation. The goal of the study of manuscripts - Philology - was to get as close a possible to that ancient knowledge.

This for example explains Newton's obsession with hidden messages and meanings in the Bible. He was convinced that the notion of gravity was already known to the ancients and was looking for clues and grounds for his own theory. Before him, it was Pythagoras who Newton thought had come closest to the mystery of the universe and had unravelled a piece of the 'harmony of the spheres'. Now gravity was a next unpuzzling of the pristine knowledge of physical nature.

Practically, in travelling and trading around the Mediterranean Sea, ancient manuscripts or information about Ur-texts were in demand too. To give an example: the Italian traveller, Pietro della Valla (1586-1652), collected information on Samaritans, Moses and the language he spoke. He even travelled to Mount Sinaï, as that was closest to the pristine knowledge and the place where the holy scriptures were first written. And just like Newton, Della Valla was also heavily inspired by Pythagoras as a traveller and collector of ancient wisdom. Extra telling is also that 17th century Copernican cosmologists were referred to as 'Phythagoreans'.

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I am not sure if the quest for ancient knowledge answers your question directly, but it might contextualise it.

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Do read these histories for a more indepth account of the examples given above:
McQuire and Rattanis, 'Newton and the Pipes of Pan', Notes and Records of the Royal Society of London, vol. 21, no. 2 (1966).
Avner Ben-Zaken, Cross-Cultural Scientific Exchanges in the Eastern Mediterranean, 1560-1660, chapter 2: 'Exchanging Heliocentrism for Ur-Text' (2010).