Firstly, it is important for people who narrate hadith, especially in Islamic classes, to have some idea of its authenticity. It is acceptable for a person who has been asked about hadith authenticity in a class to respond that they will look into it and get back to the questioner. It is unreasonable to expect every teacher in every class to know the precise reference of every hadith. However, it is reasonable to expect the teacher to look into the hadith, find the reference for it and provide it back to the questioner. Additionally, it is good practice when a teacher who knows that they will be narrating a particular hadith in class to thoroughly reference it beforehand.
With regards to referencing a hadith, a couple of points are very important. Firstly, hadtih should be referenced back to original sources, meaning a hadith book that generally has the chains of narration, not secondary or tertiary books that are narrating from those original sources. Secondly, the original source must be a well-known book from a well-known author. These two criteria must be established even before any consideration is given to the sanad (chain of narration) mentioned.
It is concerning for a learned person who has access to the Arabic books to simply reference a hadith to a contemporary scholar and not look at the actual reference of the hadith. For a learned person this methodology is absolutely clear, any traditional or even contemporary book on Islamic sciences that reliably footnotes or references hadith, will reference by and large to original sources and not a contemporary shaykh that they found quoting the hadith. Maintaining this methodology is incredibly important in order to safeguard the Sunnah of the Prophet ﷺ. If it became acceptable for people to just reference hadith to contemporary scholars and not the original sources, the whole system of hadith verification will essentially break down. The onus of referencing hadith and proving its validity is upon the person narrating it.
عَنْ أَبِي هُرَيْرَةَ قَالَ: قَالَ رَسُولُ اللهِ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ: كَفَى بِالْمَرْءِ كَذِبًا أَنْ يُحَدِّثَ بِكُلِّ مَا سَمِعَ
“Abu Hurairah said that the Prophet ﷺ said: it is enough of a lie for a person to narrate everything that he hears.” – Sahih Muslim, Chapter 3, Prohibition of Narrating Everything One Hears
Commenting on the hadith in Sahih Muslim, Imam Nawawi said:
قَالَ الْعُلَمَاءُ يَنْبَغِي لِمَنْ أَرَادَ رِوَايَةِ حَدِيثٍ أَوْ ذَكَرَهُ أَنْ يَنْظُرَ فَإِنْ كَانَ صَحِيحًا أَوْ حَسَنًا قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ كَذَا أَوْ فَعَلَهُ أَوْ نَحْوَ ذَلِكَ مِنْ صِيَغِ الْجَزْمِ وَإِنْ كَانَ ضَعِيفًا فَلَا يَقُلْ قَالَ أَوْ فَعَلَ أَوْ أَمَرَ أَوْ نَهَى وَشِبْهَ ذَلِكَ مِنْ صِيَغِ الْجَزْمِ بَلْ يَقُولُ رُوِيَ عَنْهُ كَذَا أَوْ جَاءَ عَنْهُ كَذَا أَوْ يُرْوَى أَوْ يُذْكَرُ أَوْ يُحْكَى أَوْ يقال أوبلغنا وَمَا أَشْبَهَهُ وَاللَّهُ سُبْحَانَهُ أَعْلَمُ
“The ulema have said that a person who wants to narrate a hadith or mention a hadith must look into it. If it is sahih or hasan, then he narrates it by saying the Messenger of Allah ﷺ said such and such or done such and such or the like of it using words of certainty. And if the hadith is weak, then he is not to say (the Prophet ﷺ ) said or done or commanded or prohibited or the like of that using words of certainty, rather he is to say it has been narrated regarding (the Prophet ﷺ ) or it has been mentioned regarding (the Prophet ﷺ ) or it is narrated or it is mentioned or it is said or it has reached us or the like of it. And Allah knows best.” – Imam Nawawi, Sharh Muslim, Vol. 1, pg. 71
Imam Ali al-Qari also commented on this hadith saying:
بِكُلِّ مَا سَمِعَ) : يَعْنِي: لَوْ لَمْ يَكُنْ لِلْمَرْءِ كَذِبٌ إِلَّا تَحْدِيثُهُ بِكُلِّ مَا سَمِعَ مِنْ غَيْرِ تَيَقُّنٍ أَنَّهُ صِدْقٌ أَمْ كَذِبٌ، لَكَفَاهُ مِنَ الْكَذِبِ أَنْ لَا يَكُونَ بَرِيئًا مِنْهُ، وَهَذَا زَجْرٌ عَنِ التَّحْدِيثِ بِشَيْءٍ لَمْ يُعْلَمْ صِدْقُهُ، بَلْ عَلَى الرَّجُلِ أَنْ يَبْحَثَ فِي كُلِّ مَا سَمِعَ خُصُوصًا فِي أَحَادِيثِ النَّبِيِّ – صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ
“If a person told no lie other than narrating everything he hears without verifying whether it is true or false then that is sufficient a lie for him to be guilty of it (of lying). This is a warning against narrating something that is not known to be true, rather it is incumbent upon a person to research what he hears, especially regarding hadith of the Prophet ﷺ.” – Imam Ali al-Qari, Mirqaat al-Mafaateeh, Vol. 1, pg. 240
– Answered by Shaykh Noorud-deen (05.01.2021)