The theory is that the Greek name Petra (“Rock”) replaced the biblical name Sela, which is mentioned in 2 Kings xiv. 7
1In the second year of Joash son of Joahaz king of Israel, Amaziah the son of Joash king of Judah became king…. 3 He did right in the sight of the LORD.. 5 Now it came about, as soon as the kingdom was firmly in his hand, that he killed his servants who had slain the king his father.
6 But the sons of the slayers were not put to death, but according to what is written in the book of the Law of Moses, as the LORD commanded, saying, “The fathers shall not be put to death for the sons, nor the sons be put to death for the fathers; but each shall be put to death for his own sin.”
7 And Joash killed of Edom in the Valley of Salt 10,000 and then he took Sela by war, and named it Joktheel (meaning subdued by God)
That is the first citation. The next, also on the Valley of Salt, cites 2 Chronicles xxv. Charles Stanley was the first to make the assertion that the Valley of Salt was a ravine near Petra; previously it was thought just to be a valley off the Dead Sea.
11Amaziah boldly led his army to the Valley of Salt, where he defeated 10,000 Edomites. 12The men of Judah captured 10,000 men alive. They took them to the top of a cliff and threw them over. All the captives fell to their death. 13Now the troops Amaziah had dismissed and had not allowed to fight in the battle raided the cities of Judah from Samaria to Beth Horon.
This valley (Arabah) lies between Judah and Edom on the southside of the Dead Sea. Hence some interpreters would insert the words, “and he smote Edom,” after the words, “Syrians” in the above text. It is conjectured that while David was leading his army against the Ammonites and Syrians, the Edomites invaded the south of Judah, and that David sent Joab or Abishai against them, who drove them back and finally subdued Edom. (Comp. title to Ps. 60.) Here also Amaziah “slew of Edom ten thousand men” (2 Kings 14:7; comp. 8: 20-22 and 2 Chr. 25:5-11).
Remains from the Paleolithic and Neolithic periods have been discovered at Petra, and Edomites are known to have occupied the area about 1200 BC. Centuries later the Nabataeans, an Arab tribe, occupied it and made it the capital of their kingdom. , the ruins of which are in southwest Jordan. The city was built on a terrace, pierced from east to west by the Wadi Mūsā (the Valley of Moses)—one of the places where, according to tradition, the Israelite leader Moses struck a rock and water gushed forth in Exodus (unsubstantiated).
This part of the country was assigned by tradition to the Horites, i.e. probably ” cave-dwellers,” the predecessors of the Edomites (Gen. xiv. 6, xxxvi. 20-30; Deut. ii. 12) or the descendant of Esau ; the habits of the original natives may have influenced the Nabataean custom of burying the dead and offering worship in half-excavated caves.’
The Nabateans, are considered to be the tribe of Nebaioth (Gen. xxv: 13).
13 These are the names of the sons of Ishmael, named in the order of their births: Nebaioth, the firstborn of Ishmael, and Kedar, Adbeel, Mibsam,
But that Petra itself is mentioned in the Old Testament cannot be affirmed with certainty; for though Petra is usually identified with Sela ” a rock,” as opposed to Selah (which appeared throughout the Psalms and is direction to the singers meaning “look up”). The reference in Judges i. 36; Isa. xvi. 1, xlii. 11; Obad. 3, is far from clear.
In Arabic the Greek city of Petra is Baṭrā, & centre of an Arab kingdom in Hellenistic and Roman times. The valley is enclosed by sandstone cliffs veined with shades of red and purple varying to pale yellow, and for this reason Petra was called by the 19th-century English biblical scholar John William Burgon a “rose-red city half as old as Time.”
The modern town of Wadi Mūsā, situated adjacent to the ancient city, chiefly serves the steady stream of tourists who continue to visit the site and see the Rock.