وَإِذۡ قَالَ مُوسَىٰ لِقَوۡمِهِۦ يَٰقَوۡمِ إِنَّكُمۡ ظَلَمۡتُمۡ أَنفُسَكُم بِٱتِّخَاذِكُمُ ٱلۡعِجۡلَ فَتُوبُوٓاْ إِلَىٰ بَارِئِكُمۡ فَٱقۡتُلُوٓاْ أَنفُسَكُمۡ ذَٰلِكُمۡ خَيۡرٞ لَّكُمۡ عِندَ بَارِئِكُمۡ فَتَابَ عَلَيۡكُمۡۚ إِنَّهُۥ هُوَ ٱلتَّوَّابُ ٱلرَّحِيمُ
And [recall] when Moses said to his people, ‘O my people! You have indeed wronged yourselves by taking up the Calf [for worship]. Now turn penitently to your Maker, and slay [the guilty among] your folks. That will be better for you with your Maker.’ Then He turned to you clemently. Indeed, He is the All-clement, the All-merciful.
Agha Ali Puya Commentary
Commentary on Quran 2:54
[Pooya/Ali Commentary 2:54] The outer meaning is that the righteous among the Bani Israil should get rid of the evil ones, the calf-worshippers, even if they were their own beloved kith and kin. It is stated in the Bible that three thousand persons were killed. The inner meaning could be the annihilation of selfishness, pride and other base passions. In any event, as stated here, carrying out Allah's command brings about purity and forgiveness. As stated in verse 51 of this surah those who sin, in fact, do injustice to themselves, go astray and become poorer by missing the divine mercy. (see commentary for verse 4)