For they were departed from Rephidim
After they had fought with Amalek, and came to the western part of the mount to Horeb, where the rock was smitten for them; and they were come from that now, and encamped at Sinai, after Jethro had paid a visit to Moses:
and were come to the desert of Sinai, and had pitched in this
that is, of Sinai, as in the preceding verse:
and there Israel encamped before the mount;
Mount Sinai, from whence the desert or wilderness was called. This, as Jarchi says, was on the east side of the mount; Horeb and Sinai were but one and the same mountain, which had two tops. Horeb was on the western side, near to which lay the plain of Rephidim; and Sinai was on the eastern side, on which the wilderness of that name bordered: so that the children of Israel, when they came from Rephidim, came from the western side, and took a circuit about and came to the eastern; which, according to a fore mentioned writer, was eight miles, and was the twelfth station or mansion of the children of Israel. This number twelve is taken notice of by some, as having something singular and peculiar in it; there were the twelve tribes of Israel, and at their twelfth mansion the law was given them; Christ had twelve apostles, and there are twelve foundations of the new Jerusalem, and 12,000 were sealed out of every tribe of Israel.