None of you should wish for death. Either he is a doer of good, so he may do more good; or he is an evildoer, so he may give up evil deeds. [Al-Bukhari]
"لا يَتَمَنَّ أحَدُكَم الموتَ، إما مُحسِناً فلعلَّه يَزْدَادُ، وإما مُسِيئاً فلعلَّه يَسْتَعْتِبُ" (البخاري)