Dust = Man

Biblically, there is a consistent metaphor in which dust represents Man. Man was formed of the dust and is dust and will return to dust.

And יהוה [Yahweh] Elohim [god] formed man of the dust of the ground, and breathed into his nostrils the breath of life; and man became a living soul. Genesis 2:7

... for dust thou art, and unto dust shalt thou return. Genesis 3:19

For he knoweth our frame; he remembereth that we are dust. Psalms 103:14

All go unto one place; all are of the dust, and all turn to dust again. Ecclesiastes 3:20