The interpretation timeline
Exodus 34:29 Douay-Rheims

And when Moses came down from the mount Sinai, he held the two tables of the testimony, and he knew not that his face was horned from the conversation of the Lord.

A.D. 379 – 1871 7 witnesses

Patristic

before A.D. 750
379
A.D.
Basil of Caesarea Patristic
c. A.D. 330–379
“Every soul is beautiful which is considered by the standard of its own virtues. But most beautiful, true and lovely, which can be contemplated by him alone who has purified his mind, is that of the divine and blessed nature. He who gazes steadfastly at the splendor and graces of it receives some share from it, as if from an immersion, tinging his own face with a sort of brilliant radiance. Whence Moses also was made resplendent in face by receiving some share of beauty when he held converse with God. Therefore he who is conscious of his own beauty utters this act of thanksgiving: "O Lord, in your favor, you gave strength to my beauty."”
Source

Scholastic

c. 1100 – 1500
1105
A.D.
Rashi Jewish
1040–1105
ויהי ברדת משה AND IT CAME TO PASS WHEN MOSES WENT DOWN [FROM MOUNT SINAI] — when he brought the second tablets on the Day of Atonement. כי קרן עור פניו THAT THE SKIN OF HIS FACE BEAMED — קרן is an expression connected with the word קרנים “horns”, and the phrase, קרן אור, the light-“horned” , is used here because light radiates from a point and projects Like a horn. And whence was Moses privileged to have the rays of glory? Our Rabbis said that they originated at the time when he was in the cave, for the Holy One, blessed be He, then put His hand upon his face, as it is said, (Exodus 33:22) “And I will shelter thee with My hand” (Midrash Tanchuma, Ki Tisa 37).”
Source

Post-Reformation

c. 1650 – 1900
1771
A.D.
John Gill Reformed
1697–1771
“And afterward all the children of Israel came nigh,.... That is, after Aaron and the rulers had had a conversation with Moses, then the whole body of the people by turns were admitted to come before him, and hear the laws of God from him: and he gave them in commandment all that the Lord had spoken with him on Mount Sinai; besides the two tables of stone, and the testimony written on them, he gave them all the other commands he was ordered to write in a book, and which are recorded in this chapter; he kept back nothing from them, but enjoined them to keep all the Lord had commanded.”
Source
1832
A.D.
Adam Clarke Methodist
1762–1832
“The skin of his face shone - קרן karan, was horned: having been long in familiar intercourse with his Maker, his flesh, as well as his soul, was penetrated with the effulgence of the Divine glory, and his looks expressed the light and life which dwelt within. Probably Moses appeared now as he did when, in our Lord's transfiguration, he was seen with Elijah on the mount, Matthew 17. As the original word קרן karan signifies to shine out, to dart forth, as horns on the head of an animal, or rays of light reflected from a polished surface, we may suppose that the heavenly glory which filled the soul of this holy man darted out from his face in coruscations, in that manner in which light is generally represented. The Vulgate renders the passage, et ignorabat quod cornuta esset facies sua, "and he did not know that his face was horned;" which version, misunderstood, has induced painters in general to represent Moses with two very large horns, one proceeding from each temple. But we might naturally ask, while they were indulging themselves in such fancies, why only two horns? for it is very likely that there were hundreds of these radiations, proceeding at once from the face of Moses. It was no doubt from this very circumstance that almost all the nations of the world who have heard of this transaction, have agreed in representing those men to whom they attributed extraordinary sanctity, and whom they supposed to have had familiar intercourse with the Deity, with a lucid nimbus or glory round their heads. This has prevailed both in the east and in the west; not only the Greek and Roman saints, or eminent persons, are thus represented, but those also among the Mohammedans, Hindoos, and Chinese.”
Source
1849
A.D.
1774–1849
“Horned. That is, shining, and sending forth rays of light like horns. (Challoner) — Septuagint, “encircled with glory.” St. Paul (2 Corinthians iii. 7,) says, the Hebrews could not look steadfastly at the face of Moses, on account of the glory of his countenance. Hence, he was forced to have a veil, which the apostle observes, was not taken off from the old law till Christ appeared. The Jews and heretics still read the law and the gospel with a veil over their eyes and heart, without understanding them, as they are hidden to those who perish, 2 Corinthians iv. 3. The Jews are much enraged at some Christians, who have represented Moses with horns, as if, they say, he were a devil, or his wife an adulteress. (Stacchus and Drusius.) — Hebrew, “his skin was radiant” all over his face. These rays commanded respect and awe from the people, who had before said contemptuously, Moses—the man, (chap. xxxii. 1,) as they shewed that God was with him. They had not appeared before, though he had often conversed with the Lord: but now, having seen the glorious vision, they adhered to him during the remainder of his life, particularly when he enforced the obligations of the law to the people. (Haydock) — The Arabs make their hair stand up like little horns, when they are about 40 years old. (Patric. ii. 4. Navig.) Homer mentions the like custom, and Diomed laughs at Paris calling him the pretty-horned. (Iliad xi.) Many of the ancient heroes and gods are represented with horns, particularly Bacchus, whose history reminds us of many particulars, which belong to Moses. He was born or educated in the confines of Egypt, was exposed on the waters, in a box; had two mothers, and very beautiful. While his army enjoyed the light, the Indians were in darkness. He was preceded by a pillar, had women in his train, dried up rivers with his thyrsus or wand, which had crawled, like a serpent, &c. (Huet. &c.) St. Epiphanius (her. 55,) says the Idumeans adored Moses. Their idol is called Choze by Josephus, (Antiquities xviii. 11,) which may be derived from Chus, the ancestor of Sephora, as Bacchus and Iacchus may denote “the son Bar, or the god Chus,” Jah-Chus, who was adored in Arabia; so that Moses, Choze, and Bacchus, probably mean the same person. Chus peopled that part of Arabia where the Hebrews sojourned, Numbers xii. 1. (Calmet)”
Source
1863
A.D.
1796–1863
“P. " And till Moses had done speaking." L. renders it : u After." It appears that his face was veiled whilst he spoke with them. v. 34.”
1871
A.D.
1871
“Moses wist not that the skin of his face shone while he talked with him--It was an intimation of the exalted presence into which he had been admitted and of the glory he had witnessed (Co2 3:18); and in that view, it was a badge of his high office as the ambassador of God. No testimonial needed to be produced. He bore his credentials on his very face; and whether this extraordinary effulgence was a permanent or merely temporary distinction, it cannot be doubted that this reflected glory was given him as an honor before all the people.”
Source
Modern · 1953 →

The in-app commentary runs from the Fathers to the early-modern record, then stops — that's where the public-domain sources end, not where the reading does. For the modern reading, follow the sources directly.