Numbers 21:24

from Arnon unto Jabbok, even unto the children of Ammon This gives three boundaries of Sihon's kingdom, the Jordan being the western boundary. Arnon was on the south (Numbers 21:13), Jabbok on the north, and the Ammonites on the east, whither the Amorites had driven them. The Jabbok flows into the Jordan nearly 25 miles north of the Dead Sea. The district here described is now known as the Belka-(see G. A. Smith, H. G.[Note:. G. Historical Geography of the Holy Land.] 535 f.).

for the border of the children of Ammon was strong This may be intended to explain why Sihon's territory extended no further on the east, or why the Israelites did not push their conquests further. The natural features of the country would afford no special obstacle, but the border fortresses might be impregnable. The Heb. adjective, however, is peculiar; -az(עַז) usually denotes -fierce," -cruel," rather than strong. The LXX. read the word as -Jazer," a town mentioned in Numbers 21:32; Numbers 32:3; Numbers 32:35; and it is possible that -for strong (כי עז) was the border, &c." should be emended to -at Jazer (ביעזר) was the border, &c." a statement which finds a parallel in Joshua 13:25. The words may have been a comment by the writer or a compiler on the preceding clause.