The Prophet ﷺ would not go out on the morning of ʿĪd al‑Fiṭr until he had eaten some dates — and he ate an odd number. (al-Bukhārī). It marks the end of the fast in obedience to Allah's command.

العربية: عن أنس بن مالك رضي الله عنه قال: «كان رسول الله ﷺ لا يغدو يوم الفطر حتى يأكل تمراتٍ… ويأكلهنّ وِترًا». (البخاري).

Before leaving for the ʿĪd al‑Fiṭr prayer, eat an odd number of dates — one, three or five.