Water = Spirit

Dust is dry and dirty. Water is exactly the opposite. Water cleanses and invigorates (see Purification by Water). Just as flesh is the opposite of Spirit, so dust is the opposite of water.

Water metaphorically in the Bible, represents the Spirit that flows out of Yahweh - Living water.

Yahweh, the hope of Israel, all who forsake you shall be disappointed. Those who depart from me shall be written in the earth, because they have forsaken Yahweh, the spring of living waters. Jeremiah 17:13

For I will pour water upon him that is thirsty, and floods upon the dry ground: I will pour my spirit upon thy seed, and my blessing upon thine offspring: Isaiah 44:3

But whosoever drinketh of the water that I shall give him shall never thirst; but the water that I shall give him shall be in him a well of water springing up into everlasting life. John 4:14

In the last day, that great day of the feast, Yahushua stood and cried, saying, If any man thirst, let him come unto me, and drink. He that believeth on me, as the scripture hath said, out of his belly shall flow rivers of living water. (But this spake he of the Spirit, which they that believe on him should receive: for the Holy Spirit was not yet given; because that Yahushua was not yet glorified.) John 7:37-39

We also see this metaphor in the water of the former and latter rains (outpouring of the Spirit).