إِذْ تَلَقَّوْنَهُ بِأَلْسِنَتِكُمْ
When you were propagating it with your tongues,
Mujahid and Sa`id bin Jubayr said,
"Some of you were relating it to others," where one says, `I heard this from so-and-so, and so-and-so said such and such, and some of them mentioned such and such.'
Others recited the Ayah;
إِذْ تَلِقَّوْنَهُ بِأَلْسِنَتِكُمْ
"When you were inventing a lie with your tongues..."
In Sahih Al-Bukhari, it is recorded that A'ishah recited it like that.
According to her, the meaning refers to lies which a person persists in telling.
The first recitation is preferred and more popular, and the majority recites it that way, but the second is reported from A'ishah, the Mother of the believers.
وَتَقُولُونَ بِأَفْوَاهِكُم مَّا لَيْسَ لَكُم بِهِ عِلْمٌ
and uttering with your mouths that whereof you had no knowledge,
means, you were speaking about something which you knew nothing about.
Then Allah says;
وَتَحْسَبُونَهُ هَيِّنًا وَهُوَ عِندَ اللَّهِ عَظِيمٌ
you counted it a little thing, while with Allah it was very great.
means, `you said what you said about the Mother of the believers and you thought that it was a trifling and insignificant matter, but even if she was not the wife of the Prophet, it still would not be an insignificant matter -- so how about when she is the wife of the Unlettered Prophet, the Seal of the Prophets and Leader of the Messengers!'
It is a very serious matter with Allah that such a thing should be said about the wife of His Messenger! For Allah, may He be glorified and exalted, feels great fury and anger over such matters, and He would never decree such a thing for the wife of any of His Prophets. If that is the case, then how about the best of the wives of any Prophet, the wife of the best of the sons of Adam in this world and the next Allah says;
وَتَحْسَبُونَهُ هَيِّنًا وَهُوَ عِندَ اللَّهِ عَظِيمٌ
you counted it a little thing, while with Allah it was very great.
In the Two Sahihs it is reported that;
إِنَّ الرَّجُلَ لَيَتَكَلَّمُ بِالْكَلِمَةِ مِنْ سَخَطِ اللهِ لَا يَدْرِي مَا تَبْلُغُ يَهْوِي بِهَا فِي النَّارِ أَبْعَدَ مَا بَيْنَ السَّمَاءِ وَالاَْرْضِ
A man may say a word that angers Allah without realizing how far it will go, and because of that he will be thrown into Hell a distance greater than that between heaven and earth.
According to another report;
لَاا يُلْقِي لَهَا بَالاًا
And he may not pay any attention to it.