Al-Hafiz Abu Ya`la recorded that Abu Hurayrah, may Allah be pleased with him, said, "The Messenger of Allah ﷺ said:
«مَنْ قَرَأَ يس فِي لَيْلَةٍ أَصْبَحَ مَغْفُورًا لَهُ، وَمَنْ قَرَأَ حم الَّتِي يُذْكَرُ فِيهَا الدُّخَانُ أَصْبَحَ مَغْفُورًا لَه»
(Whoever recites Ya Sin in the night, will wake up forgiven, and whoever recites Ha Mim in which Ad-Dukhan (the Smoke) is mentioned, will wake up forgiven.) Its chain of narration is good (Jayyid) . Ibn Hibban recorded in his Sahih that Jundub bin `Abdullah, may Allah be pleased with him, said, "The Messenger of Allah ﷺ said:
«مَنْ قَرَأَ يس فِي لَيْلَةٍ ابْتِغَاءَ وَجْهِ اللهِ عَزَّ وَجَلَّ غُفِرَ لَه»
(Whoever recites Ya Sin in the night, seeking the Face of Allah, will be forgiven.)
بِسْمِ اللَّهِ الرَّحْمَـنِ الرَّحِيمِ
In the Name of Allah, the Most Gracious, the Most Merciful.
We have already discussed the individual letters at the beginning of Surat Al-Baqarah.
وَالْقُرْءَانِ الْحَكِيمِ
(By the Qur'an, full of wisdom) means, Al-Muhkam (perfect) which falsehood cannot come to from before it or behind it.
إِنَّكَ
(Truly, you) means, O Muhammad,
لَمِنَ الْمُرْسَلِينَعَلَى صِرَطٍ مُّسْتَقِيمٍ
(are one of the Messengers, on the straight path.) means, following a straight methodology and religion, and an upright Law.
تَنزِيلَ الْعَزِيزِ الرَّحِيمِ
(Sent down by the Almighty, the Most Merciful.) means, this path which you have brought is a revelation from the Lord of might Who is Most Merciful to His believing servants. This is like the Ayah:
وَكَذَلِكَ أَوْحَيْنَآ إِلَيْكَ رُوحاً مِّنْ أَمْرِنَا مَا كُنتَ تَدْرِى مَا الْكِتَـبُ وَلاَ الإِيمَـنُ وَلَـكِن جَعَلْنَـهُ نُوراً نَّهْدِى بِهِ مَن نَّشَآءُ مِنْ عِبَادِنَا وَإِنَّكَ لَتَهْدِى إِلَى صِرَطٍ مُّسْتَقِيمٍ - صِرَطِ اللَّهِ الَّذِى لَهُ مَا فِى السَّمَـوَتِ وَمَا فِى الاٌّرْضِ أَلاَ إِلَى اللَّهِ تَصِيرُ الاٍّمُورُ
(And verily, you are indeed guiding (mankind) to the straight path. The path of Allah to Whom belongs all that is in the heavens and all that is on the earth. Verily, to Allah all matters return.) (42:52-53).
لِتُنذِرَ قَوْماً مَّآ أُنذِرَ ءَابَآؤُهُمْ فَهُمْ غَـفِلُونَ
(In order that you may warn a people whose forefathers were not warned, so they are heedless.) This refers to the Arabs, for no warner had come to them before him. The fact that they alone are mentioned does not mean that others are excluded, just as mentioning some individuals does not mean that all others are excluded. We have already mentioned the Ayat and Mutawatir Hadiths which state that the mission of the Prophet is universal, when we discussed the meaning of the Ayah:
قُلْ يَأَيُّهَا النَّاسُ إِنِّى رَسُولُ اللَّهِ إِلَيْكُمْ جَمِيعًا
(Say: "O mankind! Verily, I am sent to you all as the Messenger of Allah.") (7:158).
لَقَدْ حَقَّ الْقَوْلُ عَلَى أَكْثَرِهِمْ
(Indeed the Word has proved true against most of them,) Ibn Jarir said, "The punishment has become inevitable for most of them, because Allah has decreed in the Mother of the Book (Al-Lawh Al-Mahfuz) that they will not believe.
فَهُمْ لاَ يُؤْمِنُونَ
(so they will not believe. ) in Allah, or in His Messengers.