Nahj al-Balāgha
Hadith 1350وَاعْلَمْ يَا بُنَيَّ أَنَّكَ إِنَّمَا خُلِقْتَ لِلْآخِرَةِ لَا لِلدُّنْيَا، وَلِلْفَنَاءِ لَا لِلْبَقَاءِ، وَلِلْمَوْتِ لَا لِلْحَيَاةِ؛ وَأَنَّكَ فِي [مَنْزِلِ] قُلْعَةٍ، وَدارِ بُلْغَةٍ، وَطَرِيقٍ إِلَى الْآخِرَةِ، وَأَنَّكَ طَرِيدُ الْمَوْتِ الَّذِي لَا يَنْجُو مِنْهُ هَارِبُهُ، وَلَا يَفُوتُهُ طَالِبُهُ، وَلَا بُدَّ أَنَّهُ مُدْرِكُهُ، فَكُنْ مِنْهُ عَلَى حَذَرِ أَنْ يُدْرِكَكَ وَأَنْتَ عَلَى حَالٍ سَيِّئَةٍ، قَدْ كُنْتَ تُحَدِّثُ نَفْسَكَ مِنْهَا بِالتَّوْبَةِ، فَيَحُولَ بَيْنَكَ وَبَيْنَ ذلِكَ، فَإِذَا أَنْتَ قَدْ أَهْلَكْتَ نَفْسَكَ.
O my child, know that you have been created for the next world, not for this world, for destruction (in this world) not for lasting, and for dying not for living. You are in a place which does not belong to you, a house for making preparations and a passage towards the next world. You are being chased by death from which the runner-away cannot escape, as it would surely overtake him. So, be on guard against it lest it overtakes you at a time when you are in a sinful state and you are thinking of repenting but it creates obstruction between you and repentance. In such a case you will ruin yourself.