The Messenger of Allah ﷺ said, "Allah has declared upon my tongue that what lies between the two lava fields of Madinah is sacred."Then he came to the tribe of Banu Haritha and said, "Banu Haritha, I think you have moved outside the sacred precinct."Then he looked again and said, "Rather, you are within it. Rather, you are within it."
حدثنا حماد بن أسامة عن عبيد الله عن سعيد
قال رسول الله ﷺ حرم الله على لساني ما بين لابتي المدينة ثم جاء بني حارثة فقال يا بني حارثة ما أراكم إلا قد خرجتم من الحرم ثم نظر فقال بل أنتم فيه بل أنتم فيه
Its isnad is sahih. Saeed is Ibn Abu Saeed Maqburi. Bukhari related the hadith at 4:72, through the route of Sulayman bin Bilal, from Ubaydullah bin Umar, with this same isnad, in similar wording. It will come again at 8874, from Muhammad bin Ubayd, from Ubaydullah bin Umar, with the same chain, with the wording, "Allah has forbidden on my tongue what lies between the two lava fields of Madinah."His statement, "Then he came to Banu Haritha," and what follows, is part of the marfu hadith. In Bukhari's version, it reads, he said, and the Prophet ﷺ came to Banu Haritha.The meaning of the prohibition regarding Madinah has already been discussed in the hadith of Abu Hurairah at 7217, 7469, and 7740. As for the story of Banu Haritha, it is among the reports unique to Bukhari and not found in Muslim, as the Hafiz stated in Fath al-Bari 4:86.