What is the meaning of second stanza of "Lines Written in Early Spring" by William Wordsworth?

This stanza reads as follows:

To her fair works did Nature linkThe human soul that through me ran;And much it grieved my heart to thinkWhat man has made of man.

The pronoun antecedent for "her" in the first line is Nature, and that's key to understanding what the first two lines are getting at. The speaker is saying that Nature links her works to the human soul and to the speaker, specifically. He is part of the works of nature and so is every other human soul. Thus, it causes him great pain when he considers how humankind can bring such misery to other members of humankind, as we are all inextricably linked and bound through nature.
Wordsworth is ultimately conveying in these lines that humankind has a responsibility to do better in its treatment of each other because we are connected to Nature in the same ways.