Notes on the Bible, by Albert Barnes, [1834], at sacred-texts.com
Miriam, as a prophetess (compare Exo 15:20-21) no less than as the sister of Moses and Aaron, took the first rank among the women of Israel; and Aaron may be regarded as the ecclesiastical head of the whole nation. But instead of being grateful for these high dignities they challenged the special vocation of Moses and the exclusive authority which God had assigned to him. Miriam was the instigator, from the fact that her name stands conspicuously first Num 12:1, and that the punishment Num 12:10 fell on her alone. She probably considered herself as supplanted, and that too by a foreigner. Aaron was misled this time by the urgency of his sister, as once before Exo. 32 by that of the people.
The Ethiopian woman whom he had married - (Hebrew, "Cushite," compare Gen 2:13; Gen 10:6) It is likely that Zipporah Exo 2:21 was dead, and that Miriam in consequence expected to have greater influence than ever with Moses. Her disappointment at his second marriage would consequently be very great.
The marriage of Moses with a woman descended from Ham was not prohibited, so long as she was not of the stock of Canaan (compare Exo 34:11-16); but it would at any time have been offensive to that intense nationality which characterized the Jews. The Christian fathers note in the successive marriage of Moses with a Midianite and an Ethiopian a foreshadowing of the future extension to the Gentiles of God's covenant and its promises (compare Psa 45:9 ff; Sol 1:4 ff); and in the complaining of Miriam and Aaron a type of the discontent of the Jews because of such extension: compare Luk 15:29-30.
Hath the Lord ... - i. e. Is it merely, after all, by Moses that the Lord hath spoken?
The man Moses was very meek - In this and in other passages in which Moses no less unequivocally records his own faults (compare Num 20:12 ff; Exo 4:24 ff; Deu 1:37), there is the simplicity of one who bare witness of himself, but not to himself (compare Mat 11:28-29). The words are inserted to explain how it was that Moses took no steps to vindicate himself, and why consequently the Lord so promptly intervened.
Mouth to mouth - i. e. without the intervention of any third person or thing: compare the marginal references.
Even apparently - Moses received the word of God direct from Him and plainly, not through the medium of dream, vision, parable, dark saying, or such like; compare the marginal references.
The similitude of the Lord shall he behold - But, "No man hath seen God at any time," says John (Joh 1:18 : compare Ti1 6:16, and especially Exo 33:20 ff). It was not therefore the Beatific Vision, the unveiled essence of the Deity, which Moses saw on the one hand. Nor was it, on the other hand, a mere emblematic representation (as in Eze 1:26 ff, Dan 7:9), or an Angel sent as a messenger. It was the Deity Himself manifesting Himself so as to be cognizable to mortal eye. The special footing on which Moses stood as regards God is here laid down in detail, because it at once demonstrates that the supremacy of Moses rested on the distinct appointment of God, and also that Miriam in contravening that supremacy had incurred the penalty proper to sins against the theocracy.
As one dead - leprosy was nothing short of a living death, a poisoning of the springs, a corrupting of all the humors, of life; a dissolution little by little of the whole body, so that one limb after another actually decayed and fell away. Compare the notes at Lev. 13.
Heal her now, O God, I beseech thee - Others render these words: "Oh not so; heal her now, I beseech Thee."
If her father ... - i. e. If her earthly parent had treated her with contumely (compare Deu 25:9) she would feel for a time humiliated, how much more when God has visited her thus?