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Surah 71. Nuh
Ayah 2 - 4
2 قَالَ يَـٰقَوْمِ إِنِّى لَكُمْ نَذِيرٌ مُّبِينٌ
3 أَنِ ٱعْبُدُوا۟ ٱللَّهَ وَٱتَّقُوهُ وَأَطِيعُونِ
4 يَغْفِرْ لَكُم مِّن ذُنُوبِكُمْ وَيُؤَخِّرْكُمْ إِلَىٰٓ أَجَلٍ مُّسَمًّى ۚ إِنَّ أَجَلَ ٱللَّهِ إِذَا جَآءَ لَا يُؤَخَّرُ ۖ لَوْ كُنتُمْ تَعْلَمُونَ
[2-4] He said, "O my people, I am a plain warner to you. (I warn you) that you should worship Allah, and fear Him and obey me.2 Allah will forgive you your sins,3 and will give you respite till an appointed time.4 The fact is that when the appointed time of Allah comes, it cannot be deferred.5 Would that you know it."6
2The three things which the Prophet Noah presented before his people at the outset of his mission of Prophethood were:
(1) Worship of Allah,
(2) adoption of piety (taqwa) and
(3) obedience of the Messenger.
Worship of Allah meant that they should give up worship and service of all others and should acknowledge Allah alone as their Deity and should worship and carry out His commands alone. Taqwa (piety) meant that they should refrain from all those works which caused Allah's anger and displeasure, and should instead adopt such attitude in their lives as the God fearing people should adopt. As for "obey me", it meant that they should obey the commands that he gave them as Allah's Messenger.
3The sentence yaghfir la-kum min dhunub-i-kum in the original does not mean that Allah will forgive some of their sins, but its correct meaning is: "If you accept and acknowledge the three things which are being presented before you, He will forgive all the sins that you have committed in the past."
4That is, "If you accepted these three things, you would be given respite to live in the world until the time that Allah has appointed for your natural death."
5"The appointed time of Allah .. ": the time fixed by Allah for sending down a torment on a people. In this regard the Qur'an has at several places stated explicitly that when Allah's torment has been decreed for a certain people, they are not pardoned even if they affirm the faith after it.
6That is, "If you come to know fully well that the time which is now passing after you have received Allah's message through me, is, in fact, a period of respite that has been granted to you for affirming the faith-and there is no chance of escape from Allah's torment after the term of respite has elapsed-you would testify to the faith without delay and would not like to postpone it until the torment actually started descending on you."