Yes, foul language and cursing people are forbidden. The Prophet ﷺ said the believer "does not insult the honor of others, nor curse, nor commit Fahishah, nor is he foul", and that abusing a Muslim is sinful behaviour. Allah is angered by obscene speech, and good words are heavy on the scale.
The believer's tongue. "The believer does not insult the honor of others, nor curse, nor commit Fahishah, nor is
he foul" 1. "Abusing a Muslim is Fusuq (an evil doing)" 2. These are not small slips of style; they are described
as things that do not fit faith.
The Prophet's ﷺ own speech. Abdullah ibn Amr (RA) said he was never "a Fahish nor a Mutafahish", neither obscene nor
one who tried to be, and he taught that "the best among you are those who have the best manners and character" 3.
Allah dislikes obscenity. The Prophet ﷺ said nothing is heavier on the believer's scale than good character, "For
indeed Allah, Most High, is angered by the shameless obscene person" 4.
Cursing people. When Abd al-Malik ibn Marwan cursed his servant at night for being slow, Umm ad-Darda' (RA)
told him that Abu ad-Darda' (RA) had heard the Prophet ﷺ say, "The invoker of curse would neither be intercessor nor witness on the Day of Resurrection"
5. Casually saying "damn you" or cursing someone in anger is not harmless.
Words can sink or raise you. "A slave (of Allah) may utter a word which pleases Allah without giving it much
importance, and because of that Allah will raise him", and he may utter a careless word that displeases Allah and be
thrown into the Fire because of it 6.
What to do instead. Allah tells His servants to "say that which is best", because Satan uses words to stir up
conflict 7. Replace swear words gradually: pause, say "astaghfirullah" when one slips, and choose company and
content that do not normalise foul language. And remember that "speak good or keep silent" is always an option 8.
The evidence
1
HadithJami' at-Tirmidhi 1977
Sahihgraded by Al-Albani
The believer does not insult, curse, commit obscenity or speak foully.
Abdullah narrated that the Messenger of Allah said:"The believer does not insult the honor of others, nor curse, nor commit Fahishah, nor is he foul
Narrated 'Abdullah: The Prophet (ﷺ) said, "Abusing a Muslim is Fusuq (an evil doing) and killing him is Kufr (disbelief)
العربية
حَدَّثَنَا مُحَمَّدُ بْنُ عَرْعَرَةَ، قَالَ حَدَّثَنَا شُعْبَةُ، عَنْ زُبَيْدٍ، قَالَ سَأَلْتُ أَبَا وَائِلٍ عَنِ الْمُرْجِئَةِ،، فَقَالَ حَدَّثَنِي عَبْدُ اللَّهِ، أَنَّ النَّبِيَّ صلى الله عليه وسلم قَالَ " سِبَابُ الْمُسْلِمِ فُسُوقٌ، وَقِتَالُهُ كُفْرٌ ".
3
HadithSahih al-Bukhari 6029
SahihBukhari
The Prophet ﷺ was never obscene, and said the best are those with the best character.
Narrated Masruq: Abdullah bin 'Amr mentioned Allah's Messenger (ﷺ) saying that he was neither a Fahish nor a Mutafahish. Abdullah bin 'Amr added, Allah's Messenger (ﷺ) said, 'The best among you are those who have the best manners and character
العربية
حَدَّثَنَا حَفْصُ بْنُ عُمَرَ، حَدَّثَنَا شُعْبَةُ، عَنْ سُلَيْمَانَ، سَمِعْتُ أَبَا وَائِلٍ، سَمِعْتُ مَسْرُوقًا، قَالَ قَالَ عَبْدُ اللَّهِ بْنُ عَمْرٍو. حَدَّثَنَا قُتَيْبَةُ، حَدَّثَنَا جَرِيرٌ، عَنِ الأَعْمَشِ، عَنْ شَقِيقِ بْنِ سَلَمَةَ، عَنْ مَسْرُوقٍ، قَالَ دَخَلْنَا عَلَى عَبْدِ اللَّهِ بْنِ عَمْرٍو حِينَ قَدِمَ مَعَ مُعَاوِيَةَ إِلَى الْكُوفَةِ فَذَكَرَ رَسُولَ اللَّهِ صلى الله عليه وسلم فَقَالَ لَمْ يَكُنْ فَاحِشًا وَلاَ مُتَفَحِّشًا، وَقَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " إِنَّ مِنْ أَخْيَرِكُمْ أَحْسَنَكُمْ خُلُقًا ".
4
HadithJami' at-Tirmidhi 2002
Sahihgraded by Al-Albani
Nothing is heavier on the scale than good character; Allah is angered by the obscene person.
Abu Ad-Dardh narrated that the Messenger of Allah said:"Nothing is heavier on the believer's Scale on the Day of Judgment than good character. For indeed Allah, Most High, is angered by the shameless obscene person
Those who habitually curse will be neither intercessors nor witnesses on the Day of Resurrection.
Zaid b. Aslam reported that 'Abd al-Malik b. Marwan sent some domestic goods for decoration to Umm Darda' on his own behalf, and when it was night 'Abd al-Malik got up and called for the servant. It seemed as if he (the servant) was late (in responding to his call), so he ('Abd al-Malik) invoked curse upon him, and when it was morning Umm Darda' said to him:I heard you cursing your servant during the night when you called him, and she said: I heard Abu Darda' as saying that Allah's Messenger (ﷺ) said: The invoker of curse would neither be intercessor nor witness on the Day of Resurrection
A word said lightly may please Allah and raise a person, or displease Him and throw him into the Fire.
Narrated Abu Huraira:The Prophet; said, "A slave (of Allah) may utter a word which pleases Allah without giving it much importance, and because of that Allah will raise him to degrees (of reward): a slave (of Allah) may utter a word (carelessly) which displeases Allah without thinking of its gravity and because of that he will be thrown into the Hell-Fire
And tell My servants to say that which is best. Indeed, Satan induces [dissension] among them. Indeed Satan is ever, to mankind, a clear enemy
8
HadithSahih al-Bukhari 6136
SahihBukhari
Whoever believes in Allah and the Last Day should speak good or keep silent.
Narrated Abu Huraira:The Prophet (ﷺ) said, "Whoever believes in Allah and the Last Day, should not hurt his neighbor and whoever believes in Allah and the Last Day, should serve his guest generously and whoever believes in Allah and the Last Day, should speak what is good or keep silent
This answer was compiled with the help of AI, using only the verified texts shown here. Every reference links to its source. If you find a mistake, please report it. Updated 2026-09-24