Exodus 32:15

Here is, I. The favour of God to Moses, in trusting him with the two tables of the testimony, which, though of common stone, were far more valuable than all the precious stones that adorned the breast-plate of Aaron. The topaz of Ethiopia could not equal them, Exo 32:15, Exo 32:16. God himself, without the ministry either of man or angel (for aught that appears), wrote the ten commandments on these tables, on both their sides, some on one table and some on the other, so that they were folded together like a book, to be deposited in the ark. II. The familiarity between Moses and Joshua. While Moses was in the cloud, as in the presence-chamber, Joshua continued as near as he might, in the anti-chamber (as it were), waiting till Moses came out, that he might be ready to attend him; and though he was all alone for forty days (fed, it is likely, with manna), yet he was not weary of waiting, as the people were, but when Moses came down he came with him, and not till then. And here we are told what constructions they put upon the noise that they heard in the camp, Exo 32:17, Exo 32:18. Though Moses had been so long in immediate converse with God, yet he did not disdain to talk freely with his servant Joshua. Those whom God advances he preserves from being puffed up. Nor did he disdain to talk of the affairs of the camp.

— Matthew Henry's Concise Commentary (public domain)

Moses turned, and went down from the mount--The plain, Er-Raheh, is not visible from the top of Jebel Musa, nor can the mount be descended on the side towards that valley; hence Moses and his companion, who on duty had patiently waited his return in the hollow of the mountain's brow, heard the shouting some time before they actually saw the camp.

— Jamieson-Fausset-Brown Commentary (public domain)