Surah 20. Ta-Ha, Ayah 87

It is mentioned in Exodus xii, 35 that, immediately before their departure from Egypt, the Israelites "borrowed of the Egyptians jewels of silver and jewels of gold". This "borrowing" was obviously done under false pretences, without any intention on the part of the Israelites to return the jewellery to its rightful owners: for, according to the Biblical statement (ibid., verse {36}), "they spoiled [i.e., robbed] the Egyptians" by doing so. While it is noteworthy that the Old Testament, in its present, corrupted form, does not condemn this behaviour, its iniquity seems to have gradually dawned upon the Israelites, and so they decided to get rid of those sinfully acquired ornaments (Baghawi, Zamakshari and - in one of his alternative interpretations - Razi).

 The jewellery they borrowed from their Egyptian neighbours before they fled Egypt.

Cf. Exod. xii. 35-36: the Israelites, before they left Egypt, borrowed from the Egyptians "jewels of silver and jewels of gold, and raiment"; and "they spoiled the Egyptians" i.e., stripped them of all their valuable jewellery. Note that the answer of the backsliders is disingenuous in various ways. (1) The Samiri was no doubt responsible for suggesting the making of the golden calf, but they could not on that account disclaim responsibility for themselves: the burden of the sin is on him who commits it, and he cannot pretend that he was powerless to avoid it. (2) At most the weight of the gold they carried could not have been heavy even if one or two men carried it, but would have been negligible if distributed. (3) Gold is valuable, and it is not likely that if they wanted to disburden themselves of it, they had any need to light a furnace, melt it, and cast it into the shape of a calf.

See n. 2605 about the Samiri. If the Egyptian origin of the root is not accepted we have a Hebrew origin in "Shomer" a guard, watchman, sentinel. The Samiri may have been a watchman, in fact or by nickname.