فَإِنْ لَمْ تَفْعَلُوا وَلَنْ تَفْعَلُوا فَاتَّقُوا النَّارَ الَّتِي وَقُودُهَا النَّاسُ وَالْحِجَارَةُ أُعِدَّتْ لِلْكَافِرِينَ ﴿24﴾ وَبَشِّرِ الَّذِينَ آمَنُوا وَعَمِلُوا الصَّالِحَاتِ أَنَّ لَهُمْ جَنَّاتٍ تَجْرِي مِنْ تَحْتِهَا الْأَنْهَارُ كُلَّمَا رُزِقُوا مِنْهَا مِنْ ثَمَرَةٍ رِزْقًا قَالُوا هَذَا الَّذِي رُزِقْنَا مِنْ قَبْلُ وَأُتُوا بِهِ مُتَشَابِهًا وَلَهُمْ فِيهَا أَزْوَاجٌ مُطَهَّرَةٌ وَهُمْ فِيهَا خَالِدُونَ ﴿25﴾

﴾24﴿Fail lam taf'aloo wa lan taf'aloo fattaqun Naaral latee waqooduhan naasu walhijaaratu u'iddat lilkaafireen
﴾25﴿Wa bashshiril lazeena aamanoo wa 'amilus saalihaati anna lahum jannaatin tajree min tahtihal anhaaru kullamaa ruziqoo minhaa min samaratir rizqan qaaloo haazal lazee ruziqnaa min qablu wa utoo bihee mutashaabihaa, wa lahum feehaaa azwaajum mutahhara tunw wa hum feehaa khaalidoon

﴾24﴿ But if you do not do it—and you will never be able to—then protect yourselves (by accepting monotheism) from the Fire whose fuel is people (the polytheists) and stones, prepared for the disbelievers
﴾25﴿ And give glad tidings to those who have believed and acted according to the way of the Prophet (May Allah bless him and give him peace): for them are gardens beneath which rivers flow (of four types). Whenever they are provided with fruit from it to eat, they will say, “This is what we were given before,” and they will be given provision resembling it. And in Paradise, they will have pure spouses, and they will remain there forever

[24] “And you will never be able to” is a clear and enduring miracle of the Prophet (May Allah bless him and give him peace) and the Quran, as this challenge remains unmet to this day. “Then protect yourselves from the Fire” is a warning about the punishment of the Hereafter. Its fuel is people—meaning the disbelievers will burn like firewood, as mentioned in Surah Aal-Imran, verse 10. “Stones” may refer to the idols made from stone that they used to worship, or the stones placed on the graves of their leaders, which they would touch or kiss for blessings. It could also refer to sulfur stones that intensify the fire, or to ordinary stones—since in worldly fire they do not burn, this shows a unique property of the Hellfire.
[25] This is the glad tidings of the Hereafter for those who have faith and perform righteous deeds. A righteous deed is one that is supported by religious evidence and fulfills two conditions: it must be free from shirk (associating partners with Allah) and hypocrisy, and it must follow the way of the Prophet (May Allah bless him and give him peace). “This is what we were given before” has two interpretations: one is that it is a reward for the deeds for which Allah gave them success in the world, and the reward will resemble their actions. The more accepted explanation is that in Paradise, the fruits will resemble each other in appearance, but their tastes will be distinct, which is a demonstration of Allah’s power. “Spouses” refers to those companions who are perfectly compatible with their husbands—both the righteous women of this world and the heavenly maidens (houris). “Purified” means their bodies and character are free from every form of impurity and defect. “They will remain forever” means that Paradise, its fruits, and its people will never perish.