Al-A'raf - 7:85

وَإِلَى مَدْيَنَ أَخَاهُمْ شُعَيْبًا قَالَ يَا قَوْمِ اعْبُدُواْ اللّهَ مَا لَكُم مِّنْ إِلَـهٍ غَيْرُهُ قَدْ جَاءتْكُم بَيِّنَةٌ مِّن رَّبِّكُمْ فَأَوْفُواْ الْكَيْلَ وَالْمِيزَانَ وَلاَ تَبْخَسُواْ النَّاسَ أَشْيَاءهُمْ وَلاَ تُفْسِدُواْ فِي الأَرْضِ بَعْدَ إِصْلاَحِهَا ذَلِكُمْ خَيْرٌ لَّكُمْ إِن كُنتُم مُّؤْمِنِينَ
[7:85]
And to Madyan (We sent) their brother Shu'aib. He said: O my people! serve Allah, you have no god other than Him; clear proof indeed has come to you from your Lord, therefore give full measure and weight and do not diminish to men their things, and do not make mischief in the land after its reform; this is better for you if you are believers:
To the Madyan people We sent Shu'aib, one of their own brethren: he said: "O my people! worship Allah; Ye have no other god but Him. Now hath come unto you a clear (Sign) from your Lord! Give just measure and weight, nor withhold from the people the things that are their due; and do no mischief on the earth after it has been set in order: that will be best for you, if ye have Faith.
And unto Midian (We sent) their brother, Shu'eyb. He said: O my people! Serve Allah. Ye have no other Allah save Him. Lo! a clear proof hath come unto you from your Lord; so give full measure and full weight and wrong not mankind in their goods, and work not confusion in the earth after the fair ordering thereof. That will be better for you, if ye are believers.