[Machine] The Messenger of Allah ﷺ said, "No person accuses another of disbelief except that one of them will carry the burden of it, either the accuser if the accused is a disbeliever, or the accused if he falsely accuses the other."  

قَالَ رَسُولُ اللَّهِ ﷺ «مَا أَكْفَرَ رَجُلٌ رَجُلًا قَطُّ إِلَّا بَاءَ أَحَدُهُمَا بِهَا إِنْ كَانَ كَافِرًا وَإِلَّا كَفَرَ بِتَكْفِيرِهِ»  

Messenger of Allah ﷺ said, 'If anyone says to his brother, 'O misbeliever! Then surely, one of them such." (Using translation from Bukhārī 6104)  

أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ «أَيُّمَا رَجُلٌ قَالَ لِأَخِيهِ كَافِرٌ فَقَدْ بَاءَ بِهِ أَحَدُهُمَا»  

Any person who called his brother: "O unbeliever" (has in fact done an act by which this unbelief) would return to one of them. If it were so, as he asserted (then the unbelief of man was confirmed but if it was not true), then it returned to him (to the man who labeled it on his brother Muslim). (Using translation from Muslim 60b)  

قَالَ رَسُولُ اللَّهِ ﷺ «أَيُّمَا امْرِئٍ قَالَ لِأَخِيهِ كَافِرٌ فَقَدْ بَاءَ بِهِ أَحَدُهُمَا إِنْ كَانَ كَمَا قَالَ وَإِلَّا رَجَعَتْ عَلَيْهِ»