Nahj al-Balāgha
Hadith 108فإِنَّ الغَايَةَ أَمَامَكُمْ، وَإِنَّ وَرَاءَكُمُ السَّاعَةَ تَحْدُوكُمْ تَخَفَّفُواتَلْحَقوا، فَإنَّمَا يُنْتَظَرُ بِأوَّلِكُمْ آخِرُكُمْ .
Your aim (reward or punishment) is before you. Behind your back is the hour (of resurrection) which is driving you on. Keep (yourself) light and overtake (the forward ones). Your last ones are being awaited by the first ones (who have proceeded).