The first impression of arrogance is true. Whitman was proud, and felt that he was great and special, and whoever grudges him for that feeling is wrong to do so. Everyone feels that they are special and great, but no one admits it because it sounds conceited. Really, for most people it is conceited, but not for Walt Whitman because he really was as good as he saw his self.
Then he goes on to elaborate on the four sides that make up his character, the sides that make him who he is. At first he presents his self as time, personified something like God the father. He passes judgment on all who sin, in the end taking their lives. He has no mercy, only justice.
Next he presents himself as Christ, caring for the suffering, and suffering himself to spread his love for humanity. He also here writes of his immortality. Even though he may die, his words and ideas never will because they are so important.
Here in the third stanza Whitman departs from typical Christian views and includes the devil in his diety. This may look bad on the surface, but Whitman was not writing about ideals, he was writing about his self. He may have been proud, but he was not too proud to admit that there was some darker and more warlike aspects to his character. He does not portray Satan as all bad either, implying that he had sympathy for those who were oppressed (Oliver).
Lastly, he takes into account that "Holy Spirit" that Catholics and perhaps many other denominations are accustomed to. He describes it as "life", which should not be taken as lightly as some people would. "Life" does not describe the physical quality of being alive in this poem. instead it describes the emotion that being alive inspires. A person can spend entire days trying to describe just how that emotion feels, but the best anyone ever comes up with "I feel alive." That is okay. Whitman would have understood.
Whitman is explaining all of the different sides of his personality in this poem. He sees that these different sides are present in everyone else as well, although perhaps not in the same proportions. No person is one thing all of the time, and as arrogant as comparing his self to Gods sounds, the comparison is an accurate way to describe his character.
Oliver, Charles M. "'Chanting the Square Deific'." Critical Companion to Walt Whitman: A Literary Reference to His Life and Work, Critical Companion. New York: Facts On File, Inc., 2005. Bloom's Literary Reference Online. Facts On File, Inc. Web. April 3, 2012. http://www.fofweb.com/activelink2.asp?ItemID=WE54&SID=5&iPin= CCWW082&SingleRecord=True.
Whitman, Walt. "Chanting the Square Deific." The Walt Whitman Archive. Web. 03 Apr. 2012.