Abu Hurairah said; His companion came to him and said; Messenger of Allah! We have thoughts which we cannot dare talk about and we do not like that we have them or talk about them. He said:
Have you experienced that? They replied: yes. He said :
that is clear faith.
حَدَّثَنَا أَحْمَدُ بْنُ يُونُسَ، حَدَّثَنَا زُهَيْرٌ، حَدَّثَنَا سُهَيْلٌ، عَنْ أَبِيهِ، عَنْ أَبِي هُرَيْرَةَ، قَالَ جَاءَهُ نَاسٌ مِنْ أَصْحَابِهِ فَقَالُوا يَا رَسُولَ اللَّهِ نَجِدُ فِي أَنْفُسِنَا الشَّىْءَ نُعْظِمُ أَنْ نَتَكَلَّمَ بِهِ أَوِ الْكَلاَمَ بِهِ مَا نُحِبُّ أَنَّ لَنَا وَأَنَّا تَكَلَّمْنَا بِهِ . قَالَ " أَوَقَدْ وَجَدْتُمُوهُ " . قَالُوا نَعَمْ . قَالَ " ذَاكَ صَرِيحُ الإِيمَانِ " .
Grade:
Sahih
(Al-Albani)
Reference: Sunan Abi Dawud 5111
In-book reference: Book 43, Hadith 339
English translation: Book 42, Hadith 5092
https://sunnah.com/abudawud/43/339
It is narrated on the authority of Abu Huraira that some people from amongst the Companions of the Apostle (ﷺ) came to him and said:
Verily we perceive in our minds that which every one of us considers it too grave to express. He (the Holy Prophet) said: Do you really perceive it? They said: Yes. Upon this he remarked: That is the faith manifest.
حَدَّثَنِي زُهَيْرُ بْنُ حَرْبٍ، حَدَّثَنَا جَرِيرٌ، عَنْ سُهَيْلٍ، عَنْ أَبِيهِ، عَنْ أَبِي هُرَيْرَةَ، قَالَ جَاءَ نَاسٌ مِنْ أَصْحَابِ النَّبِيِّ صلى الله عليه وسلم فَسَأَلُوهُ إِنَّا نَجِدُ فِي أَنْفُسِنَا مَا يَتَعَاظَمُ أَحَدُنَا أَنْ يَتَكَلَّمَ بِهِ . قَالَ " وَقَدْ وَجَدْتُمُوهُ " . قَالُوا نَعَمْ . قَالَ " ذَاكَ صَرِيحُ الإِيمَانِ " .
Reference:
Sahih
Muslim 132 a
In-book reference: Book 1, Hadith 247
USC-MSA web (English) reference: Book 1, Hadith 239
https://sunnah.com/muslim/1/247
Imam Al-Nawawi said in his commentary on above hadeeth:
The Prophet’s words, ‘That is a clear sign of faith’ means, the fact they think of this waswaas as something terrible is a clear sign of faith, for if you dare not utter it and you are so afraid of it and of speaking of it, let alone believing it, this is the sign of one who has achieved perfect faith and who is free of doubt.
Shaytaan only whispers to those whom he despairs of tempting, because he is unable to tempt them. As for the non-Muslims, he can approach them in any manner he wants and is not restricted to waswaas, rather he can play with them however he wants. Based on this, what the hadeeth means is that the cause of waswaas is pure faith, or that waswaas is a sign of pure faith.
Waswaas happens to everyone who turns to Allah by reciting dhikr etc. It is inevitable, but you have to be steadfast and patient, and persevere with your dhikr and prayer, and not give up, because in this way you will ward off the plot of the Shaytaan.
Indeed, the plot of Satan has ever been weak[Quran 4:76]