It is the duty of every Muslim who has something to bequeath that he should not let two nights pass without having his will written down with him.
حدثنا سفيان عن أيوب عن نافع
حق على كل مسلم أن يبيت ليلتين وله ما يوصي فيه إلا ووصيته مكتوبة عنده
Its chain of transmission is sahih. It is an abridged version of 4469, but that one is mawquf while this one is marfu, and the raf is an addition from a reliable narrator.His saying, "that he should spend the night," means, "that he should not spend the night." Constructions like this are common in Arabic. The word "not" was added in the margin of manuscript K, and I am concerned that it may be an alteration introduced by a copyist or reader.