Hadith
أَخْبَرَنَا عَمْرُو بْنُ عَلِيٍّ، قَالَ حَدَّثَنَا يَحْيَى، قَالَ حَدَّثَنَا شُعْبَةُ، قَالَ حَدَّثَنَا قَتَادَةُ، عَنْ سَعِيدِ بْنِ الْمُسَيَّبِ، عَنِ ابْنِ عُمَرَ، عَنْ عُمَرَ، قَالَ سَمِعْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم يَقُولُ " الْمَيِّتُ يُعَذَّبُ فِي قَبْرِهِ بِالنِّيَاحَةِ عَلَيْهِ " .
It was narrated that 'Umar said:"I heard the Messenger of Allah say: 'The deceased is punished in his grave due to the wailing over him
Sahih · Abu Ghuddah
Sunan an-Nasa'i 1853 ·Book 21, Hadith 36·Also available on sunnah.com·