اللَّهُمَّ إِنِّي أَسْتَوْدِعُكَ مَا قَرَأْتُ وَمَا حَفِظْتُ، فَرُدَّهُ إِلَيَّ عِنْدَ حَاجَتِي إِلَيْهِ
Transliteration
Allahumma inni astawdi'uka ma qara'tu wa ma hafizt, faruddahu ilayya 'inda hajati ilayh
Translation
O Allah, I entrust to You what I have read and memorized, so return it to me when I need it.
Reference: Supplication of the scholars