Divorce - 65:11
He has sent a messenger. He recites to you the clear signs of Allah to bring those who believe and do righteous deeds out of darkness into light. Whoever believes in Allah and does righteous deeds, He will admit him into Gardens in which rivers flow, where they will abide forever. Allah has given him a goodly sustenance.
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.