Numbers 3:23 Midrash

מִשְׁפְּחֹ֖ת הַגֵּרְשֻׁנִּ֑י אַחֲרֵ֧י הַמִּשְׁכָּ֛ן יַחֲנ֖וּ יָֽמָּה׃

The families of the Gershonites were to pitch behind the tabernacle westward;

Read midrashic interpretation of Numbers 3:23: and classical rabbinic exegesis.