´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."
Hadith ReferenceSunan an-Nasa'i / The Book of Wills / Hadith: 3646
Hadith Gradingالألبانی:صحيح | زبیر علی زئی:صحيح بخاري
Hadith Takhrij«صحیح البخاری/الوصایا 1 (2738)، (تحفة الأشراف: 8382)، موطا امام مالک/الوصایا 1 (1)، مسند احمد (2/113) (صحیح)»