اللَّهُمَّ انْفَعْنِي بِمَا عَلَّمْتَنِي وَعَلِّمْنِي مَا يَنْفَعُنِي وَزِدْنِي عِلْمًا
Allahumma-nfa'ni bima 'allamtani, wa 'allimni ma yanfa'uni, wa zidni 'ilma
O Allah, benefit me from what You have taught me, teach me what will benefit me, and increase me in knowledge.
This du'a is perfect before studying or seeking any kind of knowledge. It asks for three things in a beautiful sequence: make useful what I already know, then teach me more useful things, then keep increasing my knowledge.
Related Du'as
رَبَّنَا أَتْمِمْ لَنَا نُورَنَا وَاغْفِرْ لَنَا إِنَّكَ عَلَىٰ كُلِّ شَيْءٍ قَدِيرٌ
Our Lord, perfect our light for us and forgive us. Indeed, You are over all things capable.
Sahihاللَّهُمَّ أَرِنِي الْحَقَّ حَقًّا وَارْزُقْنِي اتِّبَاعَهُ وَأَرِنِي الْبَاطِلَ بَاطِلًا وَارْزُقْنِي اجْتِنَابَهُ
O Allah, show me the truth as truth and grant me the ability to follow it, and show me falsehood as falsehood and grant me the ability to avoid it.
Hasanاللَّهُمَّ فَقِّهْهُ فِي الدِّينِ وَعَلِّمْهُ التَّأْوِيلَ
O Allah, give him deep understanding of the religion and teach him the interpretation.
Sahihاهْدِنَا الصِّرَاطَ الْمُسْتَقِيمَ صِرَاطَ الَّذِينَ أَنْعَمْتَ عَلَيْهِمْ غَيْرِ الْمَغْضُوبِ عَلَيْهِمْ وَلَا الضَّالِّينَ
Guide us to the straight path — the path of those You have blessed, not of those who earned anger, nor of those who went astray.
Sahih