Does "A prayer used SOME 2,000 years ago..." and "A prayer used ABOUT 2,000 years ago..." means the thing?
Sorry, "same thing?"

Question

Does "A prayer used SOME 2,000 years ago..." and "A prayer used ABOUT 2,000 years ago..." means the thing?
Sorry, "same thing?"

Answer

Essentially, yes.  Both sayings are an estimated guess as to when it occurred.

However, to me using "some" sounds a bit more impromptu than "about."