The Heights - 7:143
"When Moses came to us at the appointed time and his Lord spoke to him, he said, "My Lord, appear to me and let me look at you. "You cannot see me. But look at this mountain; if it stands still, then you will see me."When his Lord appeared to the mountain, He shattered it, and Moses fell unconscious. When he came to his senses, he said, "You are great, to You I turn, and I am the foremost of the believers."
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.