First sentence  painfully misguided 

A week is a time unit equal to seven days, used by the Jews at least since the time of Abraham[1], who probably lived between 2000 BCE and 1630 BCE[2].

OK, let us count the ways this makes no sense.

1) "used by the Jews at least since the time of Abraham"  since Abraham is the earliest figure in the Old Testament whom one might reasonably call a Jew, the "at least" makes no sense.

2) Abraham to the best of my knowledge is not recorded in Genesis as using a calendar of any sort. The citation attached this statement refers to Moses, an entirely different figure.

3) Abraham is a legendary figure who may or may not have existed, and who is only referred to in the books of the bible, written hundreds or thousands of years after his supposed death.  I don't want to start a fight on religion, but his historicity is certainly up for debate, and a citation of a 100-year-old encyclopedia from a religious institution based in part the Abraham narrative isn't really a reliable source.

Surely the ancient Jewish use of the seven-day week ought to be mentioned in the lede, as it is the ultimate origin of the West's seven-day week, but the first sentence as currently written is nonsense.  Any suggestions on rewrites?