In Numbers 4, the Gershonites and the Merarites had a role that wasn't as "fancy" as the role of the Kohathites. But their roles were crucial and important, even if they were more in the background.
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Ezra 6:1-13 - God Has the Right to Preserve His Word
27:13

Hebrews 10:19-25 - The Major Church Misconception Nearly Every Christian Believes
28:29

Ezra 5 - When You Are Weak, God is Strong
27:51