Hashem's glory is abundantly obvious both through His Torah and through His Creation, as Dovid HaMelech says:
The heavens recite the glory of G-d, and the sky tells of the work of His hands ... The law of Hashem is perfect, restoring the soul; the testimony of Hashem is faithful, making the simple one wise. The orders of Hashem are upright, causing the heart to rejoice; the commandment of Hashem is clear, enlightening the eyes.
The fact is, however, that often we are inspired by neither. Why not?
R' Mordecai Gifter would explain by citing the following mashal of his rebbi, Rav Mottel Pogramansky:
A group of tourists once visited the Louvre and crowded around the famous painting, the "Mona Lisa." All around people were gazing at the painting in awe. But one slovenly fellow walked in and couldn't understand what all the fuss was about. "I don't see anything so special. Some lady? Big deal!" The tour guide quietly walked over to the fellow and removed the fellow's glasses. He took out a tissue, cleaned the glasses, and placed them back on his nose. "Look again" he instructed the fellow. He watched with satisfaction as a wide smile slowly spread across the fellow's face.
Of course, Hashem's power is abundantly evident in every segment of Creation, and certainly in every part of His Torah. If we miss it, it must be that our "glasses are smudged." Tumah is obstructing our vision and interfering with the awe that should naturally wash over anyone observing His Universe or Torah.
This brings to mind another story told about the Louvre and the Mona Lisa. A tour guide was once taking a group of visitors around the museum; included among this group was an unsophisticated country bumpkin. The guide led the group to the Mona Lisa, which elicited gasps of awe expected of those who encounter the masterpiece for the first time.
The country bumpkin, however, was quite obviously unimpressed. "Why couldn't Da Vinci just decide if she was smiling or not?" The guide tried to give the fellow a quick art appreciation lesson but it was to no avail. He kept up his rant throughout the entire time at the museum. "My grandkids draw nicer than these pictures!"
In exasperation the guide turned to the fellow and said, "Listen sir. Millions of people have been through the Louvre, including the world's greatest artists and richest collectors. They have analyzed and examined every detail of these masterpieces. When you visit the Louvre, the paintings are not on trial; you are on trial. If you fail to see the beauty, then the deficiency is in you. The Louvre is not on trial."
Hashem's hand is abundantly clear in every facet of Torah and Creation. It is not on trial. If we fail to recognize it then we must conclude that we have sullied our vision with tumah and we must repair it.
Unveil my eyes that I may perceive wonders from Your Torah.