Sahih Muslim #2586

لاَ تَحَاسَدُوا وَلاَ تَنَاجَشُوا وَلاَ تَبَاغَضُوا وَلاَ تَدَابَرُوا وَلاَ يَبِعْ بَعْضُكُمْ عَلَى بَيْعِ بَعْضٍ وَكُونُوا عِبَادَ اللَّهِ إِخْوَانًا

The Messenger of Allah (ﷺ) said: 'Do not be envious of one another; do not artificially inflate prices against one another; do not hate one another; do not turn your backs on one another; and do not undercut one another in business transactions. Be, O servants of Allah, brothers.'