It is narrated from Sayyiduna Ibn Mas'ud (may Allah be pleased with him) that the Prophet (peace and blessings of Allah be upon him) said: "The mill of Islam will keep turning for thirty-five (35), thirty-six (36), or thirty-seven (37) years. After that, if the Muslims are destroyed, they will follow the path of those who were destroyed, and if they remain, their religion will last for seventy years." Sayyiduna 'Umar (may Allah be pleased with him) asked whether this pertains to the days that have passed or to the future. The Prophet (peace and blessings of Allah be upon him) said: "To the future."
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 3758
Hadith Gradingحکم دارالسلام:حديث حسن، البراء بن ناجية قد عرفه العجلي وابن حبان.