How does Hopkins prove that nature is kind and generous to us?

In "God's Grandeur," poet Gerard Manley Hopkins does not prove to us that nature is kind and generous. Instead, he makes a faith statement about God's goodness and grandeur. It is the Holy Spirit that is kind and generous, he asserts.
Hopkins notes that humankind has to some extent spoiled God's creation. He writes that

all is seared with trade; bleared, smeared with toil.

Nevertheless, he asserts that God's spirit protects the earth. Despite everything that humans have done to despoil the world, nature is "never spent," by which he means it is never used up. He also writes:

There lives the dearest freshness deep down things.

This "freshness" exists because of the Holy Spirit. Hopkins visualizes the Holy Spirit as a mixture of a mother and an angel bending over with her wings to protect the earth. This nurturing embrace coexists with God's power. Hopkins describes this power in the first stanza as flaming out like the flashes of light that occur when someone shakes a piece of foil. He also compares God's greatness to "ooze of oil crushed." He asks why we don't fear God's wrath ("reck his rod").
Although Hopkins begins with images of God's power, he chooses to end the sonnet with a comforting image of care and generosity, which is due to nature being infused with and watched over by the Holy Spirit.