Aslam, the freed slave of Sayyiduna Umar bin al-Khattab (may Allah be pleased with him), narrates from Sayyiduna Umar (may Allah be pleased with him) that he fixed a stay of three days in Madinah for the Jews, the Christians and the Magians; they would fulfil their needs, but none of them would stay more than three days.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الجزية / 18762