And assuredly We have variously propounded in this Qur'an for mankind every kind of similitude; and man is of all things the most disputing. 54 What prevents people from having faith when guidance comes to them or from asking for forgiveness from their Lord before they face the kind of torment that the ancient people experienced or a new form of torment. 55 But We send [Our] message-bearers only as heralds of glad tidings and as warners - whereas those who are bent on denying the truth contend [against them] with fallacious arguments, so as to render void the truth thereby, and to make My messages and warnings a target of their mockery. 56 Who is more unjust than he who, on being reminded of his Lord's revelations, turns away from them, and forgets the evil deeds he had committed in the past. Verily We have placed a covering on their hearts so that they do not understand, and a deafness in their ears so that however you may call them to guidance they will never be guided aright. 57 Your Lord is All-Forgiving, full of mercy. Had He wished to take them to task for their doings, He would have hastened in sending His scourge upon them. But He has set for them a time-limit which they cannot evade. 58 And (all) those townships! We destroyed them when they did wrong, and We appointed a fixed time for their destruction. 59