Tafsir of Ash-Shu`ara' 26:45

"Then Moses cast his staff, and behold, it devoured"—that is, it swallowed up with speed. The origin of al-tallaquf is to take with speed. Most of the seven [qira'at] read it as talaqqafu, with a fatha on the lam and a tashdid, the origin of which is tatalaqqafu, where one of the two ta’s was elided. The expression in the present tense is to bring the image to mind and to indicate continuity.

"What they fabricate"—that is, what they invert from its original state and form through their deception and forgery, causing their ropes and staffs to appear as snakes slithering. Ma (what) is a relative pronoun (mawsulah) whose referent is omitted due to the pause at the end of the verse. It is also permitted that it be an infinitive (masdariyyah), meaning: "it devoured their fabrication," labeling the thing fabricated with the name of the fabrication itself as an exaggeration.