1 And Miriam and Aaron spake against Moses because of the Ethiopian woman whom he had married: for he had married an Ethiopian woman. 2 And they said, Hath the LORD indeed spoken only by Moses? hath he not spoken also by us? And the LORD heard it. 3 (Now the man Moses was very meek, above all the men which were upon the face of the earth.) 4 And the LORD spake suddenly unto Moses, and unto Aaron, and unto Miriam, Come out ye three unto the tabernacle of the congregation. And they three came out. 5 And the LORD came down in the pillar of the cloud, and stood in the door of the tabernacle, and called Aaron and Miriam: and they both came forth. 6 And he said, Hear now my words: If there be a prophet among you, I the LORD will make myself known unto him in a vision, and will speak unto him in a dream. 7 My servant Moses is not so, who is faithful in all mine house. 8 With him will I speak mouth to mouth, even apparently, and not in dark speeches; and the similitude of the LORD shall he behold: wherefore then were ye not afraid to speak against my servant Moses? 9 And the anger of the LORD was kindled against them; and he departed. 10 And the cloud departed from off the tabernacle; and, behold, Miriam became leprous, white as snow: and Aaron looked upon Miriam, and, behold, she was leprous. 11 And Aaron said unto Moses, Alas, my lord, I beseech thee, lay not the sin upon us, wherein we have done foolishly, and wherein we have sinned. 12 Let her not be as one dead, of whom the flesh is half consumed when he cometh out of his mother's womb. 13 And Moses cried unto the LORD, saying, Heal her now, O God, I beseech thee. 14 And the LORD said unto Moses, If her father had but spit in her face, should she not be ashamed seven days? let her be shut out from the camp seven days, and after that let her be received in again. 15 And Miriam was shut out from the camp seven days: and the people journeyed not till Miriam was brought in again. 16 And afterward the people removed from Hazeroth, and pitched in the wilderness of Paran.
[AD 397] Ambrose of Milan on Numbers 12:1
The prophetess Mary [Miriam] herself, who crossed the straits of the sea on foot with her brothers, did not yet know the mystery of the Ethiopian [Cushite] woman and murmured against her brother Moses. She shuddered at the white spots of leprosy, which she would hardly have been freed from if Moses had not prayed for her. That murmuring stands very much as a type of the synagogue, which daily murmurs and does not grasp the mystery of the Ethiopian woman, that is, the church of the Gentiles. She envies that people by whose faith even she herself is freed from the leprosy of faithlessness, according to the verse of Scripture: “Blindness has stretched through part of Israel until the full number of Gentiles shall enter and thus shall all of Israel be saved.”

[AD 1781] Richard Challoner on Numbers 12:1
Ethiopian: Sephora the wife of Moses was of Madian, which bordered upon the land of Chus or Ethiopia: where note, that the Ethiopia here spoken of is not that of Africa but that of Arabia.
[AD 253] Origen of Alexandria on Numbers 12:2
So then in the book of Numbers we find Moses taking an Ethiopian wife—that is to say, one who is dark or black. Because of her Mary and Aaron speak ill of him and say with indignation, “Has the Lord spoken to Moses only? Has he not also spoken to us?” Now on careful consideration the narrative here seems to lack coherence. What has their saying “Has the Lord spoken to Moses only? Has he not also spoken to us?” to do with their indignation about the Ethiopian woman? If that was the trouble, they ought to have said, “Moses, you should not have taken an Ethiopian wife and one of the seed of Ham. You should have married one of your own race and of the house of Levi.” They say not a word about this. They say instead, “Has the Lord spoken to Moses only? Has he not also spoken to us?” Rather, it seems to me that in so saying they understood the thing Moses had done more in terms of the mystery. They saw Moses—that is, the spiritual law—entering now into wedlock and union with the church that is gathered together from among the Gentiles. This is the reason, apparently, why Mary [Miriam], who typified the forsaken synagogue, and Aaron, who stood for the priesthood according to the flesh, seeing their kingdom taken away from them and given to a nation bringing forth the fruits thereof, say, “Has the Lord spoken to Moses only? Has he not also spoken to us?”

[AD 253] Origen of Alexandria on Numbers 12:3
Moreover, Moses himself, in spite of all the great and splendid achievements of faith and patience that are recorded of him, was never so highly praised by God as on this occasion when he took the Ethiopian wife. It is said of him, in reference to this: “Moses was a man exceeding meek above all men that are upon earth.”

[AD 395] Gregory of Nyssa on Numbers 12:3
[Macrina replied,] It is said of Moses that he was superior to anger and desire. History testifies that he was the “meekest” of men. An incapacity for anger is shown through mildness and an aversion to wrath. He desired none of the things toward which the desiring element in many people is directed. This would not have been so if these qualities had been natural to him and logically in keeping with his essence, for it is not possible for that which is unnatural to remain in the essence. Moses, you see, was true to his essence and not involved in desire and anger, which are in addition to our nature and not our nature itself, for nature is truly that in which being has its essence.

[AD 407] John Chrysostom on Numbers 12:3
What was the characteristic of Moses of old? “Moses was the meekest of all men on earth.” One would not be wrong in describing this other Moses [i.e., Christ] in these same terms, for certainly the meekest of spirits is with him, being related to him by consubstantiality. In those days Moses stretched forth his hands to heaven and brought down the bread of angels, manna. This second Moses stretches forth his hands to heaven and brings down the food of eternal life. Moses struck the rock and made streams of water flow. This second Moses touches the table, strikes the spiritual board and makes the fountains of the Spirit gush forth. Consequently the table, like the fountain, lies in the middle, in order that the flocks may surround the fountain on every side and enjoy the benefit of the saving waters.

[AD 407] John Chrysostom on Numbers 12:3
To learn the power of gentleness and restraint, and how virtue alone suffices to render the person who practices it devotedly worthy of those ineffable encomiums, listen to the eulogy bestowed to blessed Moses. The crown was awarded him for this reason: “Moses was the mildest of all people on the earth,” Scripture says. Do you see the greatness of the encomium, which conferred on him equality of esteem with the whole human race—or, rather, gave him precedence over all humankind?

[AD 1781] Richard Challoner on Numbers 12:3
Exceeding meek: Moses being the meekest of men, would not contend for himself; therefore, God inspired him to write here his own defence: and the Holy Spirit, whose dictate he wrote, obliged him to declare the truth, though it was so much to his own praise.
[AD 99] Clement of Rome on Numbers 12:7
Moses was called “faithful in all God’s house.” God used him to bring his judgment on Egypt with scourges and torments. Yet even he, despite the great glory he was given, did not boast. But when he was granted an oracle from the bush, he said, “Who am I that you send me? I have a feeble voice and a slow tongue.” And again he says, “I am but steam from a pot.”

[AD 430] Augustine of Hippo on Numbers 12:8
As I started to say, it is shown later in the book of Numbers that even what he asked was granted to his desire, for thereby the Lord rebuked the sister of Moses for her obstinacy. The Lord appeared to the other prophets in visions and dreams but to Moses plainly and not by riddles. He added the words “And he saw the glory of the Lord.” Why then did God make such an exception of him, if not perhaps that he considered him such a ruler of his people, so faithful a minister of his whole house, that he was worthy, even then, of that contemplation, so that, as he desired, he saw God as he is—a contemplation promised to all his sons at the end of life?

[AD 407] John Chrysostom on Numbers 12:13
Miriam and her company spoke evil of Moses, and he immediately begged them off from their punishment. No, he would not so much as let it be known that his cause was avenged. But not so we. On the contrary, this is what we most desire; to have everyone know that they have not passed unpunished.

[AD 99] Clement of Rome on Numbers 12:14-15
Every kind of honour and happiness was bestowed upon you, and then was fulfilled that which is written, "My beloved ate and drank, and was enlarged and became fat, and kicked." [Deuteronomy 32:15] Hence flowed emulation and envy, strife and sedition, persecution and disorder, war and captivity. So the worthless rose up against the honoured, those of no reputation against such as were renowned, the foolish against the wise, the young against those advanced in years. For this reason righteousness and peace are now far departed from you, inasmuch as every one abandons the fear of God, and has become blind in His faith, neither walks in the ordinances of His appointment, nor acts a part becoming a Christian, but walks after his own wicked lusts, resuming the practice of an unrighteous and ungodly envy, by which death itself entered into the world. [Wisdom 2:24]

For thus it is written: "And it came to pass after certain days, that Cain brought of the fruits of the earth a sacrifice unto God; and Abel also brought of the firstlings of his sheep, and of the fat thereof. And God had respect to Abel and to his offerings, but Cain and his sacrifices He did not regard. And Cain was deeply grieved, and his countenance fell. And God said to Cain, Why are you grieved, and why is your countenance fallen? If you offer rightly, but do not divide rightly, have you not sinned? Be at peace: your offering returns to yourself, and you shall again possess it. And Cain said to Abel his brother, Let us go into the field. And it came to pass, while they were in the field, that Cain rose up against Abel his brother, and slew him." [Genesis 4:3-8] You see, brethren, how envy and jealousy led to the murder of a brother. Through envy, also, our father Jacob fled from the face of Esau his brother [Genesis 27:41-45]. Envy made Joseph be persecuted unto death, and to come into bondage. [Genesis 37:18-28] Envy compelled Moses to flee from the face of Pharaoh king of Egypt, when he heard these words from his fellow-countryman, "Who made you a judge or a ruler over us? Will you kill me, as you killed the Egyptian yesterday?" [Exodus 2:14] On account of envy, Aaron and Miriam had to make their abode without the camp. [Numbers 12:14-15] Envy brought down Dathan and Abiram alive to Hades, through the sedition which they excited against God's servant Moses. [Numbers 16:33] Through envy, David not only underwent the hatred of foreigners, but was also persecuted by Saul king of Israel. [1 Samuel 21:10-15]