سنن النسائي

It was narrated from Muhammad bin Maslamah that: When the Messenger of Allah (ﷺ) got up to offer voluntary prayers at night, he would say when he prostrated: "Allahumma laka sajadtu wa bika amantu wa laka aslamtu, Allahumma anta Rabbi, sajada wajhi lilladhi khalaqahu wa sawwarahu wa shaqqa sam'ahu wa basarahu, tabarak Allahu ahsanul-khaliqin ( O Allah, to You I have prostrated and in You I have believed and to You I have submitted. O Allah, You are my Lord. My face has prostrated to the One Who created it and formed it, and brought forth its hearing and sight. Blessed be Allah the best of Creators.)"