He who believes in Allah and the Last Day, let him not harm his neighbor
Abu Shuraih Al-Khuza'i (May Allah be pleased with him) reported:
The Prophet (may the peace and blessings of Allah be upon him) said, " He who believes in Allah and the Last Day, let him not harm his neighbor; and he who believes in Allah and the Last Day, let him show hospitality to his guest; and he who believes in Allah and the Last Day, let him either speak good or remain silent
[Muslim]
The Prophet (peace and blessings of Allah be upon him) commanded his companions - may Allah be pleased with them - and those who will come after them in this Hadeeth with three of the moral principles, because they represent the greatest descriptions of the one who completed his faith and purified his heart from the diseases of stinginess and selfishness … which disturbs the faith and extinguishes its light