Al-Baqarah - 2:54

وَإِذْ قَالَ مُوسَى لِقَوْمِهِ يَا قَوْمِ إِنَّكُمْ ظَلَمْتُمْ أَنفُسَكُمْ بِاتِّخَاذِكُمُ الْعِجْلَ فَتُوبُواْ إِلَى بَارِئِكُمْ فَاقْتُلُواْ أَنفُسَكُمْ ذَلِكُمْ خَيْرٌ لَّكُمْ عِندَ بَارِئِكُمْ فَتَابَ عَلَيْكُمْ إِنَّهُ هُوَ التَّوَّابُ الرَّحِيمُ
[2:54]
And when Musa said to his people: O my people! you have surely been unjust to yourselves by taking the calf (for a god), therefore turn to your Creator (penitently), so kill your people, that is best for you with your Creator: so He turned to you (mercifully), for surely He is the Oft-returning (to mercy), the Merciful.
And remember Moses said to his people: "O my people! Ye have indeed wronged yourselves by your worship of the calf: So turn (in repentance) to your Maker, and slay yourselves (the wrong-doers); that will be better for you in the sight of your Maker." Then He turned towards you (in forgiveness): For He is Oft-Returning, Most Merciful.
And when Moses said unto his people: O my people! Ye have wronged yourselves by your choosing of the calf (for worship) so turn in penitence to your Creator, and kill (the guilty) yourselves. That will be best for you with your Creator and He will relent toward you. Lo! He is the Relenting, the Merciful.