explanation is that Uzzah, like Eleazar before him (1 Sam 7:1), may have been consecrated to have charge of the ark, and therefore he ought to have realized that the falling of the ark was really a sign, namely, Yahweh’s way of stopping the procession (cf. the remote parallels in 1 Sam 5:1–5; 6:10–15). If so, not only the sacredness of the ark was an important factor but also the attempt (unintentional?) to frustrate or disregard the will of Yahweh; therefore also the consequences were so severe.
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