The Manifestation of Losses - 64:9
A day will come when We will gather you for the Day of gathering. This is the Day of deception. Whoever believes in Allah and does righteous deeds, He will cover his evil deeds and admit him into Gardens beneath which rivers flow. There they will abide forever. That is the great success.
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.