Ар-Рад 13:6

يَسْتَعْجِلُونَكَ بِالسَّيِّئَةِ قَبْلَ الْحَسَنَةِ وَقَدْ خَلَتْ مِن قَبْلِهِمُ الْمَثُلَاتُ ۗ وَإِنَّ رَ‌بَّكَ لَذُو مَغْفِرَ‌ةٍ لِّلنَّاسِ عَلَىٰ ظُلْمِهِمْ ۖ وَإِنَّ رَ‌بَّكَ لَشَدِيدُ الْعِقَابِ

'And they ask for evil to come sooner than good (by saying: If you are a prophet, let us have your promised punishment now - which shows that they take the coming of the Divine punishment as something very far-removed or virtually impossible) al-though punishments have really come to pass against people earlier to them, (which have been witnessed by others.)

Now, if the punishment is to come to them, why should it be taken as something far out, or impossible? Here, the word: الْمَثُلَاتُ (al-mathulat) is the plural form of مَثُلَۃ (mathula) and it means a punishment which puts a person in disgrace before everyone and proves to be a lesson for all others.

After that it was said that there is no doubt that your Lord is, de-spite the sinning and disobeying of people, the Lord of forgiveness and mercy as well. And for people who do not take advantage of this forgiveness and mercy and elect to stick to their disobedience and contumacy, then, for them He is 'severe in punishing' as well. Therefore, they should not misunderstand the attributes of Allah's forgiveness and mercy and reach the conclusion that punishment simply cannot come to them.

3. The third doubt of the disbelievers was: As for the miracles of the Holy Prophet ', they had seen many of them. But, why would he not show the specific miracles demanded by them? This has been answered in the third verse (7) by saying: وَيَقُولُ الَّذِينَ كَفَرُ‌وا لَوْلَا أُنزِلَ عَلَيْهِ آيَةٌ مِّن رَّ‌بِّهِ ۗ إِنَّمَا أَنتَ مُنذِرٌ‌ ۖ وَلِكُلِّ قَوْمٍ هَادٍ