Sunan an-Nasa'i 3616

Arabic

أَخْبَرَنَا مُحَمَّدُ بْنُ سَلَمَةَ، قَالَ حَدَّثَنَا ابْنُ الْقَاسِمِ، عَنْ مَالِكٍ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏ "‏ مَا حَقُّ امْرِئٍ مُسْلِمٍ لَهُ شَىْءٌ يُوصَى فِيهِ يَبِيتُ لَيْلَتَيْنِ إِلاَّ وَوَصِيَّتُهُ مَكْتُوبَةٌ عِنْدَهُ ‏"‏‏.‏

Translation

It was narrated from Ibn 'Umar that the Messenger of Allah said:"It is not befitting for a Muslim who has anything concerning which a will should be made, to abide for two nights without having a written will with him

Authenticity

Sahih · Abu Ghuddah

Reference