en_tn/jos/04/19.md

came up out of the Jordan

This refers to when Israel crossed the Jordan River on dry ground.

on the tenth day of the first month

This is the first month of the Hebrew calendar. The tenth day is near the end of March on Western calendars. (See: rc://en/ta/man/translate/translate-hebrewmonths and rc://en/ta/man/translate/translate-ordinal)

The twelve stones that they took out of the Jordan

Each tribe was to take one stone from the Jordan River so Joshua could build a memorial of the crossing event. (See: rc://en/ta/man/translate/figs-explicit)