Allah's Messenger (ﷺ) used to command us that as we go to our bed, we should utter these words:

اَللَّهُمَّ رَبَّ السَّمَوَاتِ وَرَبَّ الْأَرْضِ، وَرَبَّ الْعَرْشِ الْعَظِيمِ، رَبَّنَا وَرَبَّ كُلِّ شَيْءٍ، فَالِقَ الْحَبِّ وَالنَّوَى، وَمُنْزِلَ التَّوْرَاةِ وَالْإِنْجِيْلِ وَالْفُرْقَانِ، أَعُوْذُ بِكَ مِنْ شَرِّ كُلِّ شَيْءٍ أَنْتَ آخِذٌ بِنَاصِيَتِهِ، اَللَّهُمَّ أَنْتَ الْأَوَّلُ فَلَيْسَ قَبْلَكَ شَيْءٌ، وَأَنْتَ الْآخِرُ فَلَيْسَ بَعْدَكَ شَيْءٌ، وَأَنْتَ الظَّاهِرُ فَلَيْسَ فَوْقَكَ شَيْءٌ، وَأَنْتَ الْبَاطِنُ فَلَيْسَ دُونَكَ شَيْءٌ، اِقْضِ عَنَّا الدَّيْنَ وَأَغْنِنَا مِنَ الْفَقْرِ

Allaahumma Rabbas-samawaati wa Rabbal ardi, wa Rabbal-'Arshil-'Adheem, Rabbanaa wa Rabba kulli shay 'in, faaliqal-habbi wannawaa, wa munzilat-Tawraati wal-'Injeeli, wal-Furqaan, 'a'oodhu bika min sharri kulli shay'in 'Anta 'aakhidhun binaasiyatihi. Allaahumma 'Antal-'Awwalu falaysa qablaka shay'un, wa 'Antal-'Aakhiru falaysa ba'daka shay'un, wa 'Antadh-Dhaahiru falaysa fawqaka shay'un, wa 'Antal-Baatinu falaysa doonaka shay'un, iqdhi 'annad-dayna wa 'aghninaa minal-faqr

O Allah. the Lord of the Heavens and the Lord of the Earth and Lord of the Magnificent Throne, our Lord, and the Lord of evervthing, the Splitter of the grain of corn and the datestone (or fruit kernal), the Revealer of Torah and Injil and Criterion (the Holy Qur'an), I seek refuge in Thee from the evil of every- thing Thou art to sieze by the forelock (Thou hast perfect control over it). O Allah, Thou art the First, there is naught before Thee, and Thou art the Last and there is naught after Thee, and Thou art Evident and there is nothing above Thee, and Thou art Innermost and there is nothing beyond Thee. Remove the burden of debt from us and relieve us from want.

Reference: Muslim: 2713