Hadith on Major Sins: The worst sins are polytheism, disobedience to parents, killing a person without right of justice, and giving false testimony

Anas reported: The Prophet, peace be upon him, said concerning major sins, “They are associating partners with Allah, disobedience to parents, killing a person, and speaking falsehood.”
[Sahih Muslim, Book 1, Number 159]

عَنْ أَنَسٍ  عَنْ النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ فِي الْكَبَائِرِ قَالَ الشِّرْكُ بِاللَّهِ وَعُقُوقُ الْوَالِدَيْنِ وَقَتْلُ النَّفْسِ وَقَوْلُ الزُّورِ

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Hadith on Major Sins: The worst deeds are to associate partners with Allah, to disrespect parents, and to spread falsehood

Abu Bakrah reported: We were in the presence of the Messenger of Allah, peace be upon him, and he said, “Shall I inform you about the greatest of major sins? They are three: to associate partners with Allah, to disobey your parents, and to bear false witness (or he said) to speak falsely.” The Messenger of Allah, peace be upon him, was reclining and then he sat up, and he did not stop repeating this to the point that we wished he would stop.

[Sahih Muslim, Book 1, Number 158]

عَبْدُ الرَّحْمَنِ بْنُ أَبِي بَكْرَةَ عَنْ أَبِيهِ قَالَ  كُنَّا عِنْدَ رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ فَقَالَ أَلَا أُنَبِّئُكُمْ بِأَكْبَرِ الْكَبَائِرِ ثَلَاثًا الْإِشْرَاكُ بِاللَّهِ وَعُقُوقُ الْوَالِدَيْنِ وَشَهَادَةُ الزُّورِ أَوْ قَوْلُ الزُّورِ وَكَانَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ مُتَّكِئًا فَجَلَسَ فَمَا زَالَ يُكَرِّرُهَا حَتَّى قُلْنَا لَيْتَهُ سَكَتَ

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Hadith on Hypocrisy: The signs of hypocrisy are false speech, treachery, breaking promises, and evil argumentation

Abdullah ibn Umar reported: The Messenger of Allah, peace be upon him, said, “There are four signs which make someone a pure hypocrite, and whoever has them has the characteristic of hypocrisy until he abandons it: when he speaks he lies, when he makes a covenant he proves treacherous, when he makes a promise he breaks it, and when he argues he proves wicked.”
[Sahih Muslim, Book 1, Number 111]

نْ عَبْدِ اللَّهِ بْنِ عَمْرٍو قَالَ  قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ أَرْبَعٌ مَنْ كُنَّ فِيهِ كَانَ مُنَافِقًا خَالِصًا وَمَنْ كَانَتْ فِيهِ خَلَّةٌ مِنْهُنَّ كَانَتْ فِيهِ خَلَّةٌ مِنْ نِفَاقٍ حَتَّى يَدَعَهَا إِذَا حَدَّثَ كَذَبَ وَإِذَا عَاهَدَ غَدَرَ وَإِذَا وَعَدَ أَخْلَفَ وَإِذَا خَاصَمَ فَجَرَ

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