Ubaydullah bin Umar reported,

With this chain of narration, he said, "Then let him say, 'In Your name, my Lord, I lay down my side. If You take my soul, have mercy upon it.'"

Muslim 6893

Sahih

و حدثنا أبو كريب

حدثنا عبدة عن عبيد الله بن عمر

بهذا الإسناد وقال ثم ليقل باسمك ربي وضعت جنبي فإن أحييت نفسي فارحمها

مسلم 6893صحيح
Contents
Reference
Commentary
Ayat
Collection
Sahih Muslim
Book
Remembrance, supplication, Tawba, and seeking forgiveness
Chapter
What to say when sleeping and lying down
Numbering
Darussalam 6893
Muslim 6893