Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) narrated this same hadith from the Noble Prophet (peace and blessings be upon him) with the word "Islam" instead of "Deen," and in it these additional words are present: Someone asked, "Who are the unfamiliar people?" He (peace and blessings be upon him) replied, "Those who have become distant from their tribes (and relatives)."
Hadith Referenceالفتح الربانی / كتاب الإيمان و الإسلام / 168
Hadith Gradingمحدثین:صحیح
Hadith Takhrij«صحيح علي شرط مسلم۔ أخرجه الترمذي: 2629، وابن ماجه: 3988 ، (انظر مسند أحمد ترقيم الرسالة: 3784 ترقیم بيت الأفكار الدولية: 3784»
Brief Explanation
Benefits: … For such few individuals, it will be difficult to fulfill the intended objectives of Islamic rulings while remaining within their tribes; therefore, in order to achieve this purpose, they will leave their homes and families.
Or, the meaning may be that, in terms of their dealings and relationships, they will become isolated from people, even if their residences are not separate.