Mishkat al-Masabih #476
Purification
The Arabic includes the chain of narration (sanad) and the collector's commentary; the English translation shows the Prophet's words only.
وَعَنِ ابْنِ عُمَرَ قَالَ: كَانَتِ الْكِلَابُ تُقْبِلُ وَتُدْبِرُ فِي الْمَسْجِدِ فِي زَمَانِ رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ فَلَمْ يَكُونُوا يَرُشُّونَ شَيْئا من ذَلِك. رَوَاهُ البُخَارِيّ
Ibn ‘Umar said that the dogs used to go here and there in the mosque in the time of God’s messenger and that they did not sprinkle any place where they had been.
Bukhari transmitted it.
About Mishkat al-Masabih
This hadith is #476 from Mishkat al-Masabih, in the Book of Purification.