((بِاسْمِكَ رَبِّي وَضَعْتُ جَنْبِي، وَبِكَ أَرْفَعُهُ، فَإِن أَمْسَكْتَ نَفْسِي فارْحَمْهَا، وَإِنْ أَرْسَلْتَهَا فَاحْفَظْهَا، بِمَا تَحْفَظُ بِهِ عِبَادَكَ الصَّالِحِينَ)).
In Your name my Lord, I lie down and in Your name I rise, so if You should take my soul then have mercy upon it, and if You should return my soul then protect it in the manner You do so with Your righteous servants.
"If any of you rises from his bed and later returns to it, let him dust off his bed with his waist garment three times and mention the Name of Allah, for he does not know what may have entered the bed after him, and when he lies down he should say. . . ". 2 Al-Bukhari 1 1/ 126 and Muslim 4/2084.