The Messenger of Allah (PBUH) commanded us to do seven things: attend funerals, visit the sick, bless one who sneezes, accept invitations, support the oppressed, fulfill oaths, and return greetings.

Abu Bakr said: O people, you recite [yet misinterpret] this verse: {O believers! Look after your own selves. You will not be affected by those who go astray, as long as you have accepted our guidance...} [Al-Ma’idah: 105]. And I heard the Messenger of Allah (PBUH) say: If people see an evildoer and do not stop him, Allah is likely to punish them all.