فَإِذَا قَرَأْتَ الْقُرْآنَ فَاسْتَعِذْ بِاللَّهِ مِنَ الشَّيْطَانِ الرَّجِيمِ
Meaning: When you recite the Quran, seek refuge in Allah from Satan the rejected (16:98).
The imperative fasta‘idh provides the textual basis for seeking refuge before recitation. Jurists differ on whether it attaches to recitation as such or to the opening of prayer, and how it applies to the follower.