Commentaire sur Le Lévitique 24:23

ובני ישראל עשו AND THE CHILDREN OF ISRAEL DID [AS THE LORD COMMANDED MOSES] every prescription mentioned in respect to the stoning-penalty in another place, viz., the casting down of the culprit from a height, the heaping of stones upon him, and the hanging him after the execution has taken place (cf. Sifra, Emor, Chapter 19 10; Sanhedrin 43a).

AND THE CHILDREN OF ISRAEL DID AS THE ETERNAL COMMANDED MOSES. “This includes the leaning of hands,⁵⁴⁰Verse 14. casting from a height, and hanging the dead body, as well as the regulation, his body shall not remain all night upon the tree.”⁵⁴¹Deuteronomy 21:23. [This is the language of the] Torath Kohanim.⁵⁴²Torath Kohanim, end of Emor. And Rabbi Abraham ibn Ezra wrote that the plain meaning thereof is that from that day onwards they acted in accordance with the law concerning one who wounds [a fellowman or causes him damage, mentioned here above in Verses 17-21]. But it is not a correct [explanation] that this verse be referring to the future. The plain meaning thereof is as follows: “and they stoned him with stones because the children of Israel did according to the commandment which the Eternal commanded Moses.” Such a repetition of expressions is found with respect to all those who keep the commandments of G-d, just as it is said in the section of the Passover,⁵⁴³Exodus 12:28. and as He stated in the section of the census, Thus did the children of Israel; according to all that the Eternal commanded Moses, so did they;⁵⁴⁴Numbers 1:54. and so also with regards to the rods of the princes: Thus did Moses; as the Eternal commanded him, so did he.⁵⁴⁵Ibid., 17:26.
The correct interpretation here appears to me to be that since Scripture mentioned first the stoning, it went back afterwards and stated, and the children of Israel did etc., for the meaning of Scripture is to declare that when Moses spoke to the children of Israel they immediately brought forth him that had cursed, and they stoned him; and all the children of Israel did so in order to keep and fulfill [the commandment] as the Eternal commanded Moses, but not out of hatred to the son of the Egyptian who had striven with the Israelite, for [they did it] in order to remove the unworthy one from their midst.
Behar

ובני ישראל עשו כאשר צוה השם. The children of Israel did as G'd commanded. Why did the Torah write that the children of Israel did what G'd commanded after it had already reported in the first part of the verse that they took the blasphemer out of the camp and executed him by stoning him? Seeing that the cause of this execution was a quarrel between a Jew and the son of a Jewess, one could have argued that though the judgment was carried out, many people harboured reservations in their hearts about this execution. The Torah therefore repeats that the children of Israel did what G'd commanded to indicate that their motivation was to carry out G'd's commandment.