וַיֹּ֤אמֶר יְהוָה֙ אֶל־מֹשֶׁ֔ה פְּסָל־לְךָ֛ שְׁנֵֽי־לֻחֹ֥ת אֲבָנִ֖ים כָּרִאשֹׁנִ֑ים וְכָתַבְתִּי֙ עַל־הַלֻּחֹ֔ת אֶת־הַדְּבָרִ֔ים אֲשֶׁ֥ר הָי֛וּ עַל־הַלֻּחֹ֥ת הָרִאשֹׁנִ֖ים אֲשֶׁ֥ר שִׁבַּֽרְתָּ׃
The Eternal said to Moses: “Carve two tablets of stone like the first, and I will inscribe upon the tablets the words that were on the first tablets, which you shattered.
The first question: why did God command Moses to carve two tablets of stone akin to the first [set of tablets], upon which God would inscribe the Ten Commandments that were on the first set of tablets. For if the second set of tablets were to replace the first set, it would be appropriate for them to be identical in all respects; however, the first set were both carved and inscribed by God, while the second set were carved by Moses, who did not inscribe them, and inscribed by God, who did not carve them.
Malbim on Exodus 34:1:1
Carve out two stone tablets: If the first tablets had not been broken, those who studied Torah would never forget what they had learned. The Divinely fashioned tablets paralleled the angelic level of the Israelites themselves and the writing upon them symbolized the Divine word engraved upon their hearts. After the sin, however, just as the Israelites returned to the level of ordinary human beings, so were the second tablets of human origin. Nevertheless, God commanded Moshe to carve them himself, knowing that in his saintliness he would prepare them properly to receive the holy script.
Shemot Rabbah 46:1
Moses started feeling bad that he broken the tablets, so God told him: Do not feel bad about the first tablets, for they only contained the Ten Commandments, however in the second tablets that will give you, that they will have Halcahah, Midrash, and Agadah, as is said (Job 11): I will tell you hidden wisdom for it shall be double comforting.
Etz Hayyim: The first set of tablets was fashioned by God alone. Moses passively received them. The second set will be a joint divine-human effort. This second set was written with a greater knowledge of human weakness, at the hand of an imperfect human being, rather than by a perfect deity. Heschel taught that God revealed the Torah to Moses in all its fullness; and Moses, a finite human being, wrote down what he could comprehend.