Mishkat al-Masabih 28 Events of the Day of Resurrection and the Beginning of Creation كتاب أحوال القيامة وبدء الخلق 104

وَعَنْهُ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «إِنَّ فِي الْجَنَّةِ مِائَةَ دَرَجَةٍ مَا بَيْنَ كُلِّ دَرَجَتَيْنِ مِائَةُ عَامٍ» . رَوَاهُ التِّرْمِذِيُّ وَقَالَ: هَذَا حَدِيثٌ حَسَنٌ غَرِيبٌ

He reported God’s messenger as saying, “There are a hundred grades in paradise with a distance of a hundred years between every two.” Tirmidhi transmitted it, saying this is a hasan gharib tradition.