1 And all the congregation of the children of Israel journeyed from the wilderness of Sin, after their journeys, according to the commandment of the LORD, and pitched in Rephidim: and there was no water for the people to drink. 2 Wherefore the people did chide with Moses, and said, Give us water that we may drink. And Moses said unto them, Why chide ye with me? wherefore do ye tempt the LORD? 3 And the people thirsted there for water; and the people murmured against Moses, and said, Wherefore is this that thou hast brought us up out of Egypt, to kill us and our children and our cattle with thirst? 4 And Moses cried unto the LORD, saying, What shall I do unto this people? they be almost ready to stone me. 5 And the LORD said unto Moses, Go on before the people, and take with thee of the elders of Israel; and thy rod, wherewith thou smotest the river, take in thine hand, and go. 6 Behold, I will stand before thee there upon the rock in Horeb; and thou shalt smite the rock, and there shall come water out of it, that the people may drink. And Moses did so in the sight of the elders of Israel. 7 And he called the name of the place Massah, and Meribah, because of the chiding of the children of Israel, and because they tempted the LORD, saying, Is the LORD among us, or not? 8 Then came Amalek, and fought with Israel in Rephidim. 9 And Moses said unto Joshua, Choose us out men, and go out, fight with Amalek: to morrow I will stand on the top of the hill with the rod of God in mine hand. 10 So Joshua did as Moses had said to him, and fought with Amalek: and Moses, Aaron, and Hur went up to the top of the hill. 11 And it came to pass, when Moses held up his hand, that Israel prevailed: and when he let down his hand, Amalek prevailed. 12 But Moses' hands were heavy; and they took a stone, and put it under him, and he sat thereon; and Aaron and Hur stayed up his hands, the one on the one side, and the other on the other side; and his hands were steady until the going down of the sun. 13 And Joshua discomfited Amalek and his people with the edge of the sword. 14 And the LORD said unto Moses, Write this for a memorial in a book, and rehearse it in the ears of Joshua: for I will utterly put out the remembrance of Amalek from under heaven. 15 And Moses built an altar, and called the name of it Jehovah-nissi: 16 For he said, Because the LORD hath sworn that the LORD will have war with Amalek from generation to generation.
[AD 542] Caesarius of Arles on Exodus 17:3
What then does Scripture mention in what follows? “In their thirst for water, the people grumbled against Moses.” Perhaps this word that he said may seem superfluous, that the people thirsted for water. For since he said, “In their thirst,” what need was there to add “for water”? Thus indeed the ancient translation has it. Why did he add this, except because they thirsted for water when they should have thirsted for justice? “Blessed are they who hunger and thirst for justice”; and again, “thirst is my soul for the living God.” Many people are thirsty, both the just and sinners; the former thirst after justice, the latter after dissipation. The just are thirsty for God; sinners for gold. For this reason the people thirsted after water when they should have thirsted after justice.

[AD 420] Jerome on Exodus 17:4
When [Moses] was being stoned by the people, he made intercession for them. Even more so he wished to be blotted out of God’s book sooner than that the flock committed to him should perish. He sought to imitate the Shepherd who would, he knew, carry on his shoulders even the wandering sheep.

[AD 397] Ambrose of Milan on Exodus 17:6
The people of the fathers thirsted, Moses touched the rock, and water flowed out of the rock. Did not grace work a result contrary to nature, so that the rock poured forth water, which by nature it did not contain?

[AD 397] Ambrose of Milan on Exodus 17:6
It does not surpass faith that a virgin gave birth, when we read that even a rock poured out water and that the waves of the sea were made solid in the form of a wall.

[AD 542] Caesarius of Arles on Exodus 17:6
Then the Lord said to Moses, “Take the staff and strike the rock, that it may produce water for the people.” Behold, there is a rock, and it contains water. However, unless this rock is struck, it does not have any water at all. But when it has been struck, it produces fountains and rivers, as we read in the Gospel: “He who believes in me, from within him there shall flow rivers of living water.” When Christ was struck on the cross, he brought forth the fountains of the New Testament. Therefore it was necessary for him to be pierced. If he had not been struck, so that water and blood flowed from his side, the whole world would have perished through suffering thirst for the word of God.

[AD 430] Augustine of Hippo on Exodus 17:8
There is no vice which the divine law resists more [than pride]. That most proud spirit becomes an obstacle to things above and a mediator to things below. It thereby receives a greater power of domination, unless one avoids the secret snares he is laying by going along a different way. If he is openly raging through a sinful people, he is like Amalek. By his opposition he denies the passage to the land of promise. He then must be overcome by the cross of Christ, which was prefigured by the extended hands of Moses.

[AD 253] Origen of Alexandria on Exodus 17:11
For in this way, when the eyes are lifted up through thought and contemplation and the hands are lifted up in deeds which lift up and exalt the soul, as Moses lifted up his hands, one may consequently say, “The lifting up of my hands is as the evening sacrifice.” In this way the Amalekites and all the unseen enemies will be worsted, and the Israelite reasonings in us will prevail.

[AD 390] Gregory of Nazianzus on Exodus 17:11
For my own warfare, however, I am at a loss what course to pursue, what alliance, what word of wisdom, what grace to devise, with what panoply to arm myself against the wiles of the wicked one. What Moses did is to conquer him by stretching out his hands upon the mount, in order that the cross, thus typified and prefigured, may prevail.

[AD 165] Justin Martyr on Exodus 17:12
In truth it was not because Moses prayed that his people were victorious, but because, while the name of Jesus was at the battle front, Moses formed the sign of the cross. Who among you does not know that that prayer is the most pleasing to God which is uttered with lamentation and tears? But on this occasion Moses (or any after him) did not pray in such a manner; he was seated on a stone. And I have shown that even the stone is symbolical of Christ.

[AD 165] Justin Martyr on Exodus 17:12
Besides, the fact that the prophet Moses remained until evening in the form of the cross, when his hands were held up by Aaron and Hur, happened in the likeness of this sign. For the Lord also remained upon the cross until evening, when he was buried. Then he rose from the dead on the third day.

[AD 220] Tertullian on Exodus 17:12
But, to come now to Moses, why, I wonder, did he merely at the time when Joshua was battling against Amalek, pray sitting with hands expanded, when, in circumstances so critical, he ought rather, surely, to have commended his prayer by knees bent, and hands beating his breast, and a face prostrate on the ground; except it was that there, where the name of the Lord Jesus was the theme of speech—destined as he was to enter the lists one day singly against the devil—the figure of the cross was also necessary, [that figure] through which Jesus was to win the victory?

[AD 397] Ambrose of Milan on Exodus 17:12
Moses showed this when his hands became so heavy that Joshua the son of Nun could hardly hold them up. For that reason the people conquered when they performed works not carelessly but with full consideration and virtue—not with faltering souls nor with a wavering disposition but with the stability of a firm mind.

[AD 407] John Chrysostom on Exodus 17:12
See how the type was given through Moses but the truth came through Jesus Christ. And again, on Mt. Sinai, when the Amalekites were waging war on the Hebrews, the hands of Moses were propped up, held by Aaron and Hur standing on either side. But Christ, when he came, himself held his hands extended on the cross by his own power. Do you see how the type “was given” and “the truth came”?

[AD 465] Maximus of Turin on Exodus 17:12
When Moses’ hands were lifted up Amalek was conquered; when they came down a little he grew strong. The sailyards of ships and the ends of the sailyards move about in the form of our cross. The very birds, too, when they are borne to the heights and fly through the air, imitate the cross with their wings outstretched. Trophies themselves are crosses, and so are adorned victories of triumphs. These we ought to have not only on our foreheads but also on our souls so that, thus armed, we may trample upon the adder and the serpent, in Christ Jesus, to whom be glory forever.

[AD 604] Gregory the Dialogist on Exodus 17:12
When Moses sat on the stone, it prefigured the law resting on the church. But this law had heavy hands, because it did not deal mercifully with those who were sinners but treated them with extreme harshness. “Aaron” means “mountain of strength,” and “Hur” means “fire.” Who is meant by “mountain of strength”? Our Redeemer, of whom the prophet said, “It shall come to pass in the latter days that the mountain of the house of the Lord shall be established as the highest of the mountains.” And who is prefigured by “fire” but the Holy Spirit, of whom our Redeemer said, “I have come to cast fire upon the earth”? Aaron and Hur support the heavy hands of Moses and make them lighter by their support. Similarly the “Mediator between God and men,” coming with the fire of the Holy Spirit, revealed that the heavy commandments of the law, which cannot be borne when taken literally, become more tolerable for us when they are understood spiritually. It is as if he made the hands of Moses light when he changed the weight of the law’s commandments into the strength that comes from confession.