The Criterion - 25:42 "Had we not resisted, he would almost have led us astray from our gods."When they see the torment, they will know who is truly astray."
They will realize how they have gone astray when they see the torment:
The Cow/2:165 There are those who take others besides Allah as gods and love them as they love Allah. But the believers love Allah most of all. If only those wrong-doers knew that when they see the torment, they will realize that all power belongs to Allah and that Allah´s torment is severe!
The Cow/2:166 Then the followers will keep away from those who follow them, and they have seen the torment and all ties between them have been severed.
The Cow/2:167 "Those who follow will say: "If only we had had another chance, we would have shunned them as they now shun us". So Allah turns what they did into regret; they will not be able to come out of the Fire."

Prophet Jonah/10:54 If a wronged soul had all that is in the earth, it would want to ransom it. When they see the torment, they will feel deep remorse. They will be judged with justice and they will not be wronged.
Prophet Jonah/10:97 Even if all kinds of miracles come to them, they will not believe until they see the painful torment.

The Criterion/25:27 "On that Day the wrongdoer will bite his hand and say: "If only I had followed the same path with the Messenger"."
The Criterion/25:28 Woe to me, if only I had not taken so-and-so as a friend.
The Criterion/25:29 He led me astray from the message that reached me. Indeed, Satan leads a man astray.

The Stories/28:64 "We say to them, "Call your partners (for help)". So they call them, but they do not answer them. They will see the torment and burn that they were not on the right path."

The Coalition/33:66 "On the Day when their faces are turned in the Fire, they will say: "If only we had obeyed Allah, if only we had obeyed His Messenger"."

The Companies/39:58 "Or when he sees the torment, let him not say, "If only I had had a second chance, I would have been of the righteous"

The Ornaments of Gold/43:36 And whoever disregards the message of the Most Merciful, We will cause a devil to take hold of him and he will be his companion.
The Ornaments of Gold/43:37 Indeed they lead them astray. Yet they think that they are on the right path.
The Ornaments of Gold/43:38 "When he finally comes to Us, he says: "If only there had been between me and you a distance as far as the distance between two eastern countries, what an evil companion you have been!"
The Ornaments of Gold/43:39 On that Day (your repentance) will avail you nothing, for you were wrongdoers; you will share the punishment.

The Hypocrites/63:10 "Give out of what We have provided for charity before death comes to you and you say, "My Lord, if only You would postpone me for a short time so that I may be of the righteous by helping the poor"."

The Dawn/89:23 On that Day Hell will also be brought. On that Day man will understand. Then what is the use of understanding for him!
The Dawn/89:23 On that Day Hell will also be brought. On that Day man will understand. Then what is the use of understanding for him!
The Dawn/89:24 "He will say, "If only I had done something beforehand for this life."
The Dawn/89:24 "He will say, "If only I had done something beforehand for this life."