Sayyiduna Salman (may Allah be pleased with him) said: "O Arabs! You are superior to us because of two traits: 1. we do not marry your women, that is, it is not permitted; 2. and we do not lead you in prayer."
The preserved (mahfuz) version of this is mawquf (Salman's own statement).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب النكاح / 13766