Abu Dharr said (and not the Prophet): If there is not anything like the back of a saddle in front of a man who is praying, then a donkey, a black dog, and a woman cut off his prayer. I asked him: Why has the black dog been specified, distinguishing it from a red, a yellow and a white dog? He replied: My nephew, I also asked the Messenger of Allah ﷺ the same question as you asked me. He said: The black dog is a devil.
قَالَ رَسُولُ اللَّهِ ﷺ وَقَالاَ عَنْ سُلَيْمَانَ قَالَ أَبُو ذَرٍّ يَقْطَعُ صَلاَةَ الرَّجُلِ إِذَا لَمْ يَكُنْ بَيْنَ يَدَيْهِ قِيدُ آخِرَةِ الرَّحْلِ الْحِمَارُ وَالْكَلْبُ الأَسْوَدُ وَالْمَرْأَةُ فَقُلْتُ مَا بَالُ الأَسْوَدِ مِنَ الأَحْمَرِ مِنَ الأَصْفَرِ مِنَ الأَبْيَضِ فَقَالَ يَا ابْنَ أَخِي سَأَلْتُ رَسُولَ اللَّهِ ﷺ كَمَا سَأَلْتَنِي فَقَالَ الْكَلْبُ الأَسْوَدُ شَيْطَانٌ