Warnings are mentioned in the Quran in these verses:
[4:165] Messengers to deliver good news, as well as warnings. Thus, the people will have no excuse when they face God, after all these messengers have come to them. God is Almighty, Most Wise.
[10:101] Say, “Look at all the signs in the heavens and the earth.” All the proofs and all the warnings can never help people who decided to disbelieve.
[18:56] We only send the messengers as simply deliverers of good news, as well as warners. Those who disbelieve argue with falsehood to defeat the truth, and they take My proofs and warnings in vain.
[35:18] No soul can carry the sins of another soul. If a soul that is loaded with sins implores another to bear part of its load, no other soul can carry any part of it, even if they were related. The only people to heed your warnings are those who reverence their Lord, even when alone in their privacy, and observe the Contact Prayers (Salat). Whoever purifies his soul, does so for his own good. To God is the final destiny.
[38:70] “I am inspired that my sole mission is to deliver the warnings to you.”
[46:3] We did not create the heavens and the earth, and everything between them except for a specific purpose, and for a finite interim. Those who disbelieve are totally oblivious to the warnings given to them.
[46:21] Recall that the brother of `Aad warned his people at the dunes – numerous warnings were also delivered before him and after him: “You shall not worship except God. I fear for you the retribution of a great day.”
[46:22] They said, “Did you come to divert us from our gods? We challenge you to bring (the retribution) you threaten, if you are truthful.”
[46:23] He said, “The knowledge about this is with God; I only deliver to you what I was sent to deliver. However, I see that you people are ignorant.”
[46:24] When they saw the storm heading their way, they said, “This storm will bring to us much needed rain.” Instead, this is what you challenged (Hood) to bring; violent wind wherein there is painful retribution.
[46:25] It destroyed everything, as commanded by its Lord. By morning, nothing was standing except their homes. We thus requite the guilty people.
[46:26] We had established them in the same way as we established you, and provided them with hearing, eyes, and minds. But their hearing, eyes, and minds did not help them at all. This is because they decided to disregard God’s revelations. Thus, the prophecies and warnings that they ridiculed have caused their doom.
[50:45] We are fully aware of everything they utter, while you have no power over them. Therefore, remind with this Quran, those who reverence My warnings.
[54:4] Sufficient warnings have been delivered to alert them.
[54:5] Great wisdom; but all the warnings have been in vain.
[54:16] How terrible was My retribution after the warnings!
[54:17] We made the Quran easy to learn. Does any of you wish to learn?
[54:18] `Aad disbelieved. Consequently, how terrible was My retribution after the warnings.
[54:19] We sent upon them violent winds, on a day of continuous misery.
[54:20] It tossed the people around as if they were decayed palm tree trunks.
[54:21] How terrible was My retribution after the warnings!
[54:22] We made the Quran easy to learn. Does any of you wish to learn?
[54:23] Thamoud rejected the warnings.
[54:33] The people of Lot rejected the warnings.
[54:34] We showered them with rocks. Only Lot’s family was saved at dawn.
[54:35] We blessed him and his family; we thus reward the appreciative.
[54:36] He warned them about our requital, but they ridiculed the warnings.
[77:1] (Angels) dispatched in succession.
[77:2] To drive the wind.
[77:3] Stir up clouds.
[77:4] Distribute the provisions.
[77:5] Deliver messages.
[77:6] Good news, as well as warnings.
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