The Banishment - 59:9
Those who had a home and a faith before them love those who emigrated to them and do not feel bitterness in their hearts because of what they have given. Even if they themselves are in need, they put them before themselves. Indeed, those who are protected from the selfishness of their souls are the saved.
The most important criterion of belief:
The Cattle/6:82
Those who believe and do not mix their faith with wrongdoing, they deserve security and they have found the truth.
Luqman/31:13
"When Lokman advised his son, he said: "My dear son, do not associate partners with Allah; surely shirk (associating partners with God) is a great wrong."
The Companies/39:65
It has been revealed to you and those before you that if you associate partners, all that you do will be in vain and you will be of the losers.