مَنِّي النَّفْسَ وَعِدِيهَا وَاجْمَعِي الرِّقَاعَ وَعُدِّيهَا
Give yourself hope and promises, and gather and count the written slips.
ʿIdīhā / ʿuddīhā look very similar in unvowelled writing, but vowels and gemination produce two instructions: promise or encourage, and count. Abū Zayd asks the woman both to cultivate hope and to count the written slips.
The joke depends on actual morphological distinctions, not simply a playful noise. Misreading both as the same verb would lose an entire practical command. This is why careful vocalisation is indispensable in classical Arabic wordplay.