1 Then came the children of Israel, even the whole congregation, into the desert of Zin in the first month: and the people abode in Kadesh; and Miriam died there, and was buried there. 2 And there was no water for the congregation: and they gathered themselves together against Moses and against Aaron. 3 And the people chode with Moses, and spake, saying, Would God that we had died when our brethren died before the LORD! 4 And why have ye brought up the congregation of the LORD into this wilderness, that we and our cattle should die there? 5 And wherefore have ye made us to come up out of Egypt, to bring us in unto this evil place? it is no place of seed, or of figs, or of vines, or of pomegranates; neither is there any water to drink. 6 And Moses and Aaron went from the presence of the assembly unto the door of the tabernacle of the congregation, and they fell upon their faces: and the glory of the LORD appeared unto them. 7 And the LORD spake unto Moses, saying, 8 Take the rod, and gather thou the assembly together, thou, and Aaron thy brother, and speak ye unto the rock before their eyes; and it shall give forth his water, and thou shalt bring forth to them water out of the rock: so thou shalt give the congregation and their beasts drink. 9 And Moses took the rod from before the LORD, as he commanded him. 10 And Moses and Aaron gathered the congregation together before the rock, and he said unto them, Hear now, ye rebels; must we fetch you water out of this rock? 11 And Moses lifted up his hand, and with his rod he smote the rock twice: and the water came out abundantly, and the congregation drank, and their beasts also. 12 And the LORD spake unto Moses and Aaron, Because ye believed me not, to sanctify me in the eyes of the children of Israel, therefore ye shall not bring this congregation into the land which I have given them. 13 This is the water of Meribah; because the children of Israel strove with the LORD, and he was sanctified in them. 14 And Moses sent messengers from Kadesh unto the king of Edom, Thus saith thy brother Israel, Thou knowest all the travail that hath befallen us: 15 How our fathers went down into Egypt, and we have dwelt in Egypt a long time; and the Egyptians vexed us, and our fathers: 16 And when we cried unto the LORD, he heard our voice, and sent an angel, and hath brought us forth out of Egypt: and, behold, we are in Kadesh, a city in the uttermost of thy border: 17 Let us pass, I pray thee, through thy country: we will not pass through the fields, or through the vineyards, neither will we drink of the water of the wells: we will go by the king's highway, we will not turn to the right hand nor to the left, until we have passed thy borders. 18 And Edom said unto him, Thou shalt not pass by me, lest I come out against thee with the sword. 19 And the children of Israel said unto him, We will go by the high way: and if I and my cattle drink of thy water, then I will pay for it: I will only, without doing any thing else, go through on my feet. 20 And he said, Thou shalt not go through. And Edom came out against him with much people, and with a strong hand. 21 Thus Edom refused to give Israel passage through his border: wherefore Israel turned away from him. 22 And the children of Israel, even the whole congregation, journeyed from Kadesh, and came unto mount Hor. 23 And the LORD spake unto Moses and Aaron in mount Hor, by the coast of the land of Edom, saying, 24 Aaron shall be gathered unto his people: for he shall not enter into the land which I have given unto the children of Israel, because ye rebelled against my word at the water of Meribah. 25 Take Aaron and Eleazar his son, and bring them up unto mount Hor: 26 And strip Aaron of his garments, and put them upon Eleazar his son: and Aaron shall be gathered unto his people, and shall die there. 27 And Moses did as the LORD commanded: and they went up into mount Hor in the sight of all the congregation. 28 And Moses stripped Aaron of his garments, and put them upon Eleazar his son; and Aaron died there in the top of the mount: and Moses and Eleazar came down from the mount. 29 And when all the congregation saw that Aaron was dead, they mourned for Aaron thirty days, even all the house of Israel.
[AD 585] Cassiodorus on Numbers 20:1
Next comes “And the Lord shall shake the desert of Kadesh.” This still refers to the spirit of piety. The account in Numbers carefully explains this reference when it tells how the people of Israel came to Kadesh and were suffering from excessive thirst because of the aridity of that place. Moses struck a rock at the Lord’s command and suddenly provided an abundance of water for them. In a remarkable way the earth, which lay foul with unwatered dustiness, was irrigated. By this comparison the prophet says that the most obdurate hearts of sinners can be liquefied into waters of wisdom. The example of Kadesh must be reenacted in human hearts. The term desert is often used of places where unfaithful people are known to gather, as the Gospel says: “The voice of one crying in the desert.” John could not have preached in the desert where none could hear. Rather, “desert” is used to describe those who had not as yet apprehended the gifts of faith.

[AD 379] Basil of Caesarea on Numbers 20:10
The people were murmuring because there was no water. Moses merely had said to his people, “Can we bring you forth water out of this rock?” Thus he wavered only slightly, yet for this alone he immediately received the threat that he should not enter into the land of promise, which was at that time the chief of all the promises made to the Jews. When I behold this man asking and not obtaining pardon, when I see him not deemed worthy of forgiveness because of those few words, even in consideration of so many righteous deeds, truly I discern, in the words of the apostle, “the severity of God.” I am fully persuaded that these words are true: “If the just man shall scarcely be saved, where shall the ungodly and the sinner appear?”

[AD 420] Jerome on Numbers 20:11
Priests also must take care lest they be insincere, lest they doubt the power of God. If Aaron and Moses (who seemed to waver at the waters of contradiction) did not deserve to enter the Promised Land, does it not stand to reason that we, bent under the burden of sin, shall be far less able to cross the river Jordan and reach Gilgal, the place of circumcision, if we shall cause one of these little ones to sin?

[AD 430] Augustine of Hippo on Numbers 20:11
The rock is Christ in a sign, the true Christ in the Word and in the flesh. And how did they drink? The rock was struck twice with a rod. The double striking prefigures the two pieces of wood on the cross.

[AD 430] Augustine of Hippo on Numbers 20:11
We recognize that we are taking a trip in a wasteland. If we recognize ourselves in a wasteland, we are in a wasteland. What does it mean, in a wasteland? In a desert. Why in a desert? Because in this world, one thirsts on a waterless road. But let us thirst that we may be filled. For “blessed are they who hunger and thirst for justice; for they shall have their fill.” And our thirst is filled from a rock in the wasteland. For “the rock was Christ.” And it was struck with a rod that water might flow. But that it might flow, it was struck twice; for there are the two pieces of wood on the cross.

[AD 542] Caesarius of Arles on Numbers 20:11
“Therefore Moses struck the rock twice with his staff.” What does this mean, brethren? I do not think it is without mystery. What does it mean that the rock was not struck once but twice with the staff? The rock was struck a second time because two trees were lifted up for the gibbet of the cross: the one stretched out Christ’s sacred hands, the other spread out his sinless body from head to foot.

[AD 1781] Richard Challoner on Numbers 20:11
The rock: This rock was a figure of Christ, and the water that issued out from the rock, of his precious blood, the source of all our good.
[AD 1781] Richard Challoner on Numbers 20:12
You have not believed: The fault of Moses and Aaron, on this occasion, was a certain diffidence and weakness of faith; not doubting of God's power or veracity; but apprehending the unworthiness of that rebellious and incredulous people, and therefore speaking with some ambiguity.
[AD 1781] Richard Challoner on Numbers 20:13
The Water of contradiction: Or strife. Hebrew, Meribah.
[AD 390] Gregory of Nazianzus on Numbers 20:17
So in the case of one of us, if he leans to either side, whether from vice or ignorance, no slight danger of a fall into sin from vice or ignorance, no slight danger of a fall into sin is incurred, both for himself and those who are led by him. But we must really walk in the king’s highway and take care not to turn aside from it either to the right hand or to the left, as the Proverbs say. For such is the case with our passions, and such in this matter is the straight path of the good shepherd, if he is to know properly the souls of his flock, and to guide them according to the methods of a pastoral care which is right and just and be worthy of our true Shepherd.

[AD 397] Ambrose of Milan on Numbers 20:26
What else does it mean that after the death of Aaron God did not command the entire people but only Moses, who is among the priests of the Lord, to clothe with the vestments of Aaron the priest his son, Eleazar, unless we understand that a priest should consecrate a priest? He himself should vest him, that is, with priestly virtues. And then, if he sees that he lacks none of the priestly vestments and that everything is appropriately in order, he admits him to the holy altars.