He mentioned it by two names. Al-Kisa’i said: “The Criterion is an epithet of the Book, and the conjunction is superfluous”; that is, the Book which distinguishes between what is lawful and what is forbidden. Yaman ibn Rabban said: By “the Criterion” He meant the parting of the sea, as He says, “And when We parted the sea for you and saved you.” “So that you might be guided” through the Torah.
“And when Moses said to his people”—those who had worshipped the calf—“O my people, you have wronged yourselves”: you have harmed yourselves “by taking the calf” as a god. They said, “What then should we do?” He said, “So repent”—that is, return—“to your Creator.” They asked, “How are we to repent?” He said, “Then kill yourselves,” meaning that the innocent among you should kill the guilty. “That is”—that is, this killing—“better for you in the sight of your Creator.”
When Moses commanded them to kill, they said, “We shall patiently submit to Allah’s command.” They sat in the courtyards (1), with their knees drawn up (2), and were told: “Whoever loosens his binding, looks toward his killer, or attempts to ward him off with hand or foot, is accursed, and his repentance shall be rejected.” The people then turned their daggers against them. A man would see his son, father, brother, relative, friend, or neighbor, yet they could not bring themselves to carry out Allah’s command. They said, “O Moses, how are we to do this?” Thereupon Allah, exalted is He, sent upon them a mist and a dark cloud, so that they could not see one another, and they went on killing them until evening. When the killing became widespread, Moses and Aaron, peace be upon them, supplicated, wept, and implored Allah, saying, “Our Lord, the Children of Israel have perished! Spare the remnant, spare the remnant!” Then Allah, exalted is He, removed the cloud and commanded them to cease the killing. It cleared away from thousands of slain.
It is related from Ali, may Allah be pleased with him, that he said: The number of those slain was seventy thousand. This weighed heavily upon Moses, so Allah, exalted is He, revealed to him: “Would it not please you that I admit both the killer and the slain into Paradise?” Thus, whoever among them was killed was a martyr, while the sins of whoever remained were expiated. This is the meaning of His saying, exalted is He: “Then He accepted your repentance”—that is, when you did what you had been commanded, He accepted your repentance and pardoned you. “Indeed, He is the Accepter of repentance,” the One who accepts repentance, “the Most Merciful” to His creation.
“And when you said, ‘O Moses, we will never believe you until we see Allah openly,’ so the thunderbolt struck you while you were looking on. Then We restored you to life after your death, so that you might give thanks. And We shaded you with clouds and sent down upon you manna and quails: ‘Eat of the wholesome things We have provided for you.’ They did not wrong Us; rather, they wronged themselves.”
His saying, exalted is He: “And when you said, ‘O Moses, we will never believe you until we see Allah openly’”: this was because Allah, exalted is He, commanded Moses, peace be upon him, to come to Him with a group from the Children of Israel, who would seek His pardon for their worship of the calf. So Moses selected seventy men.