«اِللِّي شَافْ شِيءْ يِحْكِي عَلِيهْ»

Reporting an event is treated here as the job of an eyewitness. Firsthand sight is what gives someone the standing to recount what happened, and that standing does not pass to people who were absent from the scene.

The saying addresses a mismatch between a request and the person receiving it: someone is being asked for an account of a matter they never observed and know nothing about. Invoking it marks that person as having nothing to report.

Appropriate when someone asks you to describe or explain a matter you neither witnessed nor learned anything about. The proverb answers by noting that an account properly comes from a person who actually saw the thing, which you did not.