Musnad Ahmed: Hadith 3735

The Messenger of Allah (ﷺ) said: "Verily the millstone of Islam will stop turning after thirty-five (years) or thirty-six or thirty-seven, then if they perish (after deviating) they will meet the same fate as those who perished (before them), but if they persist (in following the right path) then they will be in a good state for seventy years." 'Umar said: O Messenger of Allah, (seventy years) including that or seventy years in addition to that? He said: "In addition to that."