Frankenstein by Mary Shelley, Volume 2, chapter 1: What does the magnificent beautiful surroundings that Victor is in when on a boat in the lake...

In Mary Shelley's Frankenstein, Victor finds himself at home in Geneva once more, after his young brother William has been murdered. The grandeur of nature has always seemed to inspire Victor, but at this particular moment, the magnificence of his surroundings escapes him.

I was often tempted, when all was at peace around me, and I the only unquiet thing that wandered restless in a scene so beautiful and heavenly...I was tempted to plunge into the silent lake, that the waters might close over me and my calamities forever.

At another point in the story, after Justine's wrongful conviction and execution for William's death, Victor takes in all the beauties of nature around him, and he reflects:

The immense mountains and precipices that overhung me on every side, the sound of the river raging among the rocks, and the dashing of the waterfalls around spoke of a power mighty as Omnipotence—and I ceased to fear or to bend before any being less almighty than that which had created and ruled the elements, here displayed in their most terrific guise.

One of the things that so strikes me about Victor's story is a predominate theme in the novel regarding man's presumption to act like God, creating life (and from dead flesh, at that)—which is the horrific sin that Victor has committed. Although his reasons were pure, Shelley is quick to point to the power of the Almighty, the One who created the world—only God is the Creator—how could man ever possess such hubris to believe he could rival the power of God—and go unpunished?

"Nature and its subversion" is a major theme in the story. Victor has not only given life to dead flesh, but he has also robbed graveyards (an illegal act) and created what all in the world of medicine and science (of that time) would consider an abomination. It is only after Victor comes to his senses that he realizes the enormity of his actions, and then he abandons the creature, taking no responsibility for his creation.

In the segment where he acknowledges the magnificence of nature and declares that he will only fear "Omnipotence...that which created and ruled the elements" (God), it is easy to understand that Victor feels out of place in nature. For the mountains, rocks, waterfalls, etc.,  are very much God's house, His cathedral, a holy place that testifies to His "almighty power." I believe it has a humbling and shaming effect upon Victor when he confronts God in His glory (nature).

My opinion, in light of Victor's sins against God and mankind, is that he is most aware of the depth of his horrific acts and finds it most difficult to face not only the knowledge of his terrible sins, but also realization that he created the thing that murdered his young, innocent brother William.

Ironically, in nature where Victor feels so close to God, I believe it is eventually also where he feels most remote from his Creator. His own guilt separates him from feeling at ease in the presence of God.