How far could Jews walk on the Sabbath in the Mosaic law versus present-day Judaism?
The Mosaic law did not originally set a Sabbath walking-distance limit. Present-day Judaism, by contrast, restricts Sabbath walking to roughly a mile or a mile and a half. That restriction would make a long flight on the Sabbath especially difficult, as the context explains concerning a future escape from Jerusalem.
Les explains that in Jesus’ day the restriction was not originally part of the Mosaic law. The Mosaic law did not limit how far someone could walk on the Sabbath, but present-day Judaism does, limiting it to something like a mile or a mile and a half. He connects this to Jesus’ warning that the Jews should pray their flight does not occur on a Sabbath day, because they will have to go many miles. That flight, he says, will be like Israel leaving Egypt on Passover night. The exodus from Egypt had to be miraculous: they walked, but God must have moved them along to travel from Goshen to the Red Sea in a short time. Les sees the same pattern at the midpoint of the Tribulation, when Jews in Jerusalem realize the one they trusted, who signed the treaty three and a half years earlier, is their mortal enemy. They will congregate and flee Jerusalem, and an earthquake will occur that same day.