The Lord gave clear instructions in his Word as to how the ark was to be transported (Numbers 4:4–6, Numbers 4:15, Numbers 4:17–20; Numbers 7:9). Refusing to submit to those instructions showed a lack of reverence for the ark and the Lord.1 This will be the third time in Samuel that the Lord demonstrates that he can defend the ark himself (see 1 Samuel 5:3–12; 1 Samuel 6:19–20).2
7 And the anger of the LORD was kindled against Uzzah, and God struck him down there because of his error, and he died there beside the ark of God.