He slew of Edom in the valley of Salt ten
Of which valley, (See Gill on 2 Samuel 8:13), the Edomites having revolted from Judah in the days of Joram, ( 2 Kings 8:20 2 Kings 8:22 ) . Amaziah undertook to reduce them with an army of 300,000 choice men; and, besides these, hired also of Israel 100,000 valiant men, for one hundred talents of silver; but at the instance of a prophet of the Lord he dismissed the latter, and went against Edom only with his men, and slew of the Edomites 10,000, besides other 10,000 he took alive, and cast headlong from a rock, which came into his hands, see ( 2 Chronicles 25:5-12 ) ,
and took Selah by war;
which signifies a rock, the same with Petra, the metropolis of Arabia Petraea, the country of the Edomites. The city itself was not a rock, nor built on one, but was situated in a plain, surrounded with rocks and mountains, as Strabo F26 and Pliny F1 relate, from whence it seems to have its name; and by the Syrians called Recem, where Rocan a king of Midian reigned F2, called in the Greek version of ( Numbers 31:8 ) , Recon; though Vitringa F3 is of opinion, that not Petra, the metropolis of Edom, is meant, but Maalehakrabbim, ( Joshua 15:3 ) ( Judges 1:36 ) , which lay on the south border of Judea, near the salt sea:
and called the name of it Joktheel;
which signifies "the obedience of God"; in memory of his obedience to the prophet of the Lord, in consequence of which he obtained this victory: and the name continued unto this day: the time of the writing this book.