«وَأَنْشَبْتُ شِصِّي فِي كُلِّ شِيصَةٍ»
I lodged my hook in every shīṣah.
Shiṣṣ is a hook used for catching; shīṣah refers to an inferior or undeveloped date. Their similar sounds create conspicuous verbal play.
The later metaphor of preaching as a snare clarifies the image: he describes his efforts through the language of catching and securing what he seeks.