Rock
As a result, the rocks of Palestine repeatedly play a part in the Bible story, and the book is also rich in metaphors which follow from Moses’ first Biblical reference to God as a Rock (Deut 32:4). (1) In the unsettled state of this region in Old Testament times, it was a sensible precaution to use the natural defensive quality of rocky sites to build fortress cities. So great were the natural advantages of such sites for defense that many of these fortresses were to all intents impregnable, given the military techniques of the period; siege or treachery offered the only hopes of capture. (2) The rock offered shelter from the storm (whether actual or figurative). The limestones of Palestine are full of caves, and thus we find David hiding from Saul in the cave of Adullam (1 Sam 22:1) or the rocks around En-gedi (24:1-3). (3) The rock served as a source of water to Israel in the wilderness (Exod 17:6; Num 20:11). It is a well-known feature of limestone terrain that water seeps down through crevices to break out at unexpected points in the form of springs; God evidently guided Moses to points where this could take place.
In the symbolism of the Bible, God is the Rock of His people (Moses, who first used the metaphor, had had an unusually wide experience of rocks!) and the New Testament transfers the image to make Christ the Rock from which His people drank (1 Cor 10:4). Some commentators, taking this into account, have seen a spiritual significance in the fact that the rock Moses was commanded to strike (Exod 17) was tsūr, the lowly rock, corresponding to the stricken and suffering Christ, while in Numbers 20 he was told only to speak to the rock (here sēlâ, the high rock) and made the mistake of striking it on this occasion too: they see in this a picture of the exalted Christ, who suffered only once to accomplish our salvation and is now glorified.
Additional Material
Source 1
International Standard Bible Encyclopedia (1915)
((1) cela`; (2) tsur (3) challamish, "flint"; compare Arabic khalanbus, "flint"; (4) kephim (Job 30:6;" Jer 4:29); compare Kephas, "Cephas" = Petros, "Peter" (Joh 1:42 the King James Version and the Revised Version margin); (5) petra):
1. Names:
Tsur and cela` are the words most often found, and there is no well-defined distinction between them. They are frequently coupled together in the parallelism which is characteristic of the Hebrew writers: e.g.
"Be thou to me a strong rock (tsur),
A house of defense to save me.
For thou art my rock (tsela) and my fortress"
(Ps 31:2,3).
"He clave rocks (tsur) in the wilderness,
And gave them drink abundantly as out of the depths.
He brought streams also out of the rock (sela),
And caused waters to run down like rivers"
(Ps 78:15,16).
It is plain here that the two words are used for the sake of variety, without any clear difference of meaning. Even challamish (translated "flint") is used in the same way with tsur in Ps 114:8:
"Who turned the rock (tsur) into a pool of water;
The flint (callamish) into a fountain of waters."
2. Figurative:
(2) The rocks are a refuge, both figuratively and literally (Jer 48:28; So 2:14); "The rocks are a refuge for the conies" (Ps 104:18). Many a traveler in Palestine has felt the refreshment of "the shade of a great rock in a weary land" (Isa 32:2). A very different idea is expressed in Isa 8:14, "And he shall be for a sanctuary; but for a stone of stumbling and for a rock of offense" (compare Ro 9:33; 1Pe 2:8).
(3) The rock is a symbol of hardness (Jer 5:3; compare Isa 50:7). Therefore, the breaking of the rock exemplifies the power of God (Jer 23:29; compare 1Ki 19:11). The rock is also a symbol of that which endures, "Oh that they .... were graven in the rock for ever!" (Job 19:23,24). A rock was an appropriate place for offering a sacrifice (Jud 6:20; 13:19). The central feature of the Mosque of `Umar in Jerusalem is Qubbat-uc-Cakhrat, the "dome of the rock." The rock or cakhrat under the dome is thought to be the site of Solomon’s altar of burnt offering, and further is thought to be the site of the threshing-floor of Araunah the Jebusite which David purchased to build an altar to Yahweh.
3. Kinds of Rock:
(1) The principal rock of Palestine and Syria is limestone of which there are many varieties, differing in color, texture, hardness and degrees of impurity, some of the limestone having considerable admixtures of clay or sand. Some of the harder kinds are very dense and break with a conchoidal fracture similar to the fracture of flint. In rocks which have for ages been exposed to atmospheric agencies, erosion has produced striking and highly picturesque forms. Nodules and layers of flint are of frequent occurrence in the limestone.
(2) Limestone is the only rock of Western Palestine, with the exception of some local outpourings of basaltic rock and with the further exception of a light-brown, porous, partly calcareous sandstone, which is found at intervals along the coast. This last is a superficial deposit of Quaternary or recent age, and is of aeolian origin. That is, it consists of dune sands which have solidified under the influence of atmospheric agencies. This is very exceptional, nearly all stratified rocks having originated as beds of sand or mud in the bottom of the sea.
(3) In Sinai, Edom, Moab, Lebanon and Anti-Lebanon is found the Nubian sandstone, a silicious sandstone which, at least in the North, is of middle or lower Cretaceous age. In the South, the lower strata of this formation seem to be paleozoic. Most of it is not sufficiently coherent to make good building stone, though some of its strata are very firm and are even used for millstones. In some places it is so incoherent or friable that it is easily dug with the pick, the grains falling apart and forming sand that can be used in mortar. In color the Nubian sandstone is on the whole dark reddish brown, but locally it shows great variation, from white through yellow and red to black. In places it also has tints of blue. The celebrated rock tombs and temples of Petra are carved in this stone.
(4) Extensive areas of the northern part of Eastern Palestine are covered with igneous rock. In the Jaulan Southeast of Mt. Hermon, this has been for ages exposed to the atmosphere and has formed superficially a rich dark soil. Further Southeast is the Leja’ (Arabic "refuge"), a wild tract covered with a deposit of lava which is geologically recent, and which, while probably earlier than man, is still but little affected by the atmosphere. It is with difficulty traversed and frequently furnishes an asylum to outlaws.