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Surah 7. Al-A'raf
Ayah 148 - 149
١٤٨. وَٱتَّخَذَ قَوْمُ مُوسَىٰ مِنۢ بَعْدِهِۦ مِنْ حُلِيِّهِمْ عِجْلًا جَسَدًا لَّهُۥ خُوَارٌ ۚ أَلَمْ يَرَوْا۟ أَنَّهُۥ لَا يُكَلِّمُهُمْ وَلَا يَهْدِيهِمْ سَبِيلًا ۘ ٱتَّخَذُوهُ وَكَانُوا۟ ظَـٰلِمِينَ
١٤٩. وَلَمَّا سُقِطَ فِىٓ أَيْدِيهِمْ وَرَأَوْا۟ أَنَّهُمْ قَدْ ضَلُّوا۟ قَالُوا۟ لَئِن لَّمْ يَرْحَمْنَا رَبُّنَا وَيَغْفِرْ لَنَا لَنَكُونَنَّ مِنَ ٱلْخَـٰسِرِينَ
148. And the people of Musa made in his absence, out of their ornaments, the image of a calf (for worship). It had a sound. Did they not see that it could neither speak to them nor guide them to the way They took it (for worship) and they were wrongdoers. 149. And when they regretted and saw that they had gone astray, they said: "If our Lord have not mercy upon us and forgive us, we shall certainly be of the losers''
Allah describes the misguidance of those who worshipped the calf that As-Samiri made for them from the ornaments they borrowed from the Copts. He made the shape of a calf with these ornaments and threw in it a handful of dust from the trace of the horse that the Angel Jibril was riding, and the calf seemed to moo. This occurred after Musa went for the appointed term with his Lord, where Allah told him about what happened when he was on Mount Tur. Allah said about His Honorable Self,
((Allah) said: "Verily, We have tried your people in your absence, and As-Samiri has led them astray'') ﴿20:85﴾. The scholars of Tafsir have different views over the calf, whether it actually became alive and mooing, or if it remained made of gold, but the air entering it made it appear to be mooing. These are two opinions. Allah knows best. It was reported that when the statue mooed, the Jews started dancing around it and fell into misguidance because they adored it. They said that this, the calf, is your god and the god of Musa, but Musa forgot it! Allah answered them,
(Did they not see that it could not return them a word (for answer), and that it had neither power to harm them nor to do them good) ﴿20:89﴾. Allah said here,
(Did they not see that it could neither speak to them nor guide them to the way) Allah condemned the Jews for falling into misguidance, worshipping the calf and ignoring the Creator of the heavens and earth, the Lord and King of all things. They worshipped besides Him a statue made in the shape of a calf, that seemed to moo, but it neither spoke to them nor brought them any benefit. Rather, their very sense of reason was blinded because of ignorance and misguidance. Allah's statement,
(And when they regretted), and felt sorrow for their action,
(and saw that they had gone astray, they said: "If our Lord have not mercy upon us and forgive us, we will certainly become among the losers.'') or among the destroyed ones. This was their recognition of their sin and their way of seeking salvation from Allah the Most Mighty and Majestic.