וַיֹּ֛אמֶר אֶל־בְּנֵ֥י יִשְׂרָאֵ֖ל לֵאמֹ֑ר אֲשֶׁר֩ יִשְׁאָל֨וּן בְּנֵיכֶ֤ם מָחָר֙ אֶת־אֲבוֹתָ֣ם לֵאמֹ֔ר מָ֖ה הָאֲבָנִ֥ים הָאֵֽלֶּה׃
And he spoke unto the children of Israel, saying: ‘When your children shall ask their fathers in time to come, saying: What mean these stones?
Read commentary on Joshua 4:21, verse-by-verse classical interpretation.