Have linguistics found any evidence that Semitic languages influenced Germanic languages or vice versa (in ancient times)?
BACKGROUND: I suggested to a forum of linguists that a certain Semitic word (attested to in Hebrew and Aramaic) is the basis for a similar-sounding Germanic word which essentially means the same thing. They rejected my proposal on the grounds that they know of no early interactions between Semitic and Gemanic peoples, see here for the discussion.
There are some very controversial theories by the German linguist Theo Vennemann postulating a contact between Phoenician and proto-Germanic in the 6th to 3rd century BCE. The evidence for such contact is very thin and most linguists don't follow Vennemann.
The specific question on the origin of the word God was asked here before, and the consensus is that the word God derives from proto-Indogermanic and is not a loan from Hebrew or Aramaic. Such chance coincidences occur very often between any pair of languages.
No - however that doesn't mean semitic words which described man-made goods did not enter the Proto-germanic wordstore when that good was traded - words such as this are known as 'Wanderwörter' or 'wandering words'.
The Akkadian (the oldest known semitic language spoken in Babylon) word for silver was 'kaspum'. When refining was discovered refined silver was known as 'kaspum ṣurpum' ('ṣarāpum' meant 'to refine') or just 'ṣurpum'.
'ṣurpum' seems to have been the source for the proto-germanic word '*silubra' from which comes English 'silver' and German 'Silber'.
However I can see no good reason to suggest that the word 'god' is such a Wanderwort.
I concur with @Ned - e.g. Matasovic in "Areal Typology of Proto‐Indo‐European: The Case for Caucasian Connections" mentions trade between Sumerian folks, North Caucasians and Yamana culture. In my humble opinion an important objective of trade was slavery, so even if the trade was indirect through intermediaries, language would have been brought along anyway.
By the way, for gada you might want to take a look at Egyptian "dd" - stability, common Anglicization Djed.
Consider a current theory for "god" as from a Lombardic "godan", variant of "Odin", a Germanic deity, also "Wotan", which wiktionary gives derived from *weh₂t-. Compare that to "veda" and above "mwt". That's not comprehensive nor coherent, but mighty interesting. Note *weh₂t- is linked to Old English ƿoþ /woːθ/ - sound, noise, cry, '''speech''', articulation, eloquence, song, poetry, voice. But more so Ger. "Wut" - strong emotion; cp. "rush", "rage" with "rushes, reeds" and "papyrus" and the like.
