The Disbelievers thought that the Day of Resurrection would never come to pass

Allah tells us how the disbelievers thought that the Day of Resurrection would never come to pass, as they said:

مَتَى هَـذَا الْوَعْدُ

Commentary

مَا يَنظُرُ‌ونَ إِلَّا صَيْحَةً وَاحِدَةً (They are looking for nothing but for a single Cry that will seize them - 36:49). The question of the disbelievers quoted here is the one they used to'-ask the Muslims by way of mockery, and the real purpose was to deny the Day of Judgment. It was not asked for finding out the truth, nor as a serious effort to reach the reality. It was simply a way of taunting the Muslims and making fun of them. And even if it were for finding out the true nature of the event, then, the mercy of the Lord of the universe requires that the full and precise knowledge of the year and day of the coming of Qiyamah should not be given to anyone, so much so that it was not given even to any one from among His noble prophets and messengers. Even if this question asked by these dimwit people was no more than a fact-finding exercise on their part, it was patently absurd. Therefore, rather than tell them, in response, the time when Qiyamah will come, they were admonished. They were told that reasonable people, once they become aware of something that is bound to come in all certainty, should start making necessary preparations ahead of it, and not go about wasting precious time in trying to find out its precise hour and day. Common sense required that, once they had heard the foreboding of Qiyamah, they should have believed and did what it takes to achieve success in that life to come. But, so entangled they are in their heedlessness that they virtually seem to be waiting for nothing short of the time when the day of Qiyamah comes before them - and then, they would think about it. Therefore, it was said that these people were waiting for the Qiyamah - while, Qiyamah will have a scenario of its own, for it would be just one terrible sound of the Horn صُور (Sur) that will seize everyone all of a sudden in a way that people will be busy in their businesses settling their disputes and they all, in this very condition, will lie dead.