1 Cor 10:1-4 wrote:For I do not want you to be unaware, brothers, that our fathers were all under the cloud, and all passed through the sea, and all were baptized into Moses in the cloud and in the sea, and all ate the same spiritual food, and all drank the same spiritual drink. For they drank from the spiritual Rock that followed them, and the Rock was Christ.
Exodus 17 and Numbers 20 have nearly identical accounts, 40 years apart, of Moses producing water from a rock. In both cases the people were without water and accused Moses of bringing them out of Egypt just to kill them with thirst in the desert. In both cases Moses took his staff and struck the rock (though the second time God told him only to speak, holding the staff in his hand), and water flowed from the rock, in sufficient quantity to quench the thirst of the people and animals. In both cases the name Meribah was given.
There are at least 3 logical possibilities for the water supply in the intervening 40 years:
1. They traveled from one oasis to another.
2. The rock stayed put at Rephidim, but water continued to flow from it to supply their needs (see Psalm 105:41).
3. The rock moved with them (see 1 Cor 10:4), providing a continuous water supply.
The first option is straightforward. The second option is also not too hard to accept, given a 40 year supply of manna, which also apparently followed them. It does not explain, however, how Moses knew which rock to speak to; Numbers appears to refer to a specific rock that Moses and the people had no problem identifying.
Does the third option sound a bit strange? It does not have any Old Testament support, but there are Jewish writings that describe it, and then of course there are the words of Paul, who would likely have been aware of those writings and may have been alluding to them, taking them a step further in applying them to Christ.
A few examples of this tradition in the Rabbinic writings:
Tosephta Sukka wrote:And so the well which was with the Israelites in the wilderness was a rock, the size of a large round vessel, surging and gurgling upward, as from the mouth of its little flask, rising with them up onto the mountains, and going down with them into the valleys. Wherever the Israelites would encamp, it made camp with them, on a high place, opposite the entry of the Tent of Meeting. The princes of Israel come and surround it with their staffs, and they sing a song concerning it: Spring up, O Well!
Targum Pseudo-Jonathon wrote:And because it (the rock) was given to them as a gift, it turned to ascend the high mountains with them and from the high mountains it descended with them to the valleys, going around the entire camp of Israel and giving them drink each and every one of them at the door of his tent.
Have you heard this before? Do you think it's all wet? What was Paul referring to?