Stephen Crane reveals Jack Potter's character set against two very different backdrops. What are they? How does he conduct himself in each setting?

In “The Bride Comes to Yellow Sky” by Stephen Crane, the reader experiences Jack Potter’s character on the train as a newlywed, and in the rural Texas outpost town named Yellow Sky.
When the story opens, Jack Potter is riding the train back to Yellow Sky with his new bride. Earlier in the day, the couple was married in San Antonio. Jack shows his wife how worldly he is by explaining things about train travel, and treating her to a meal in the dining car. He is a bit shy in his new role as a husband but shows concern for his bride as they travel back to Yellow Sky where he is the town marshal. His speech is quiet but informative.

"You see, it's a thousand miles from one end of Texas to the other, and this train runs right across it and never stops but four times." He had the pride of an owner. He pointed out to her the dazzling fittings of the coach, and in truth her eyes opened wider as she contemplated the sea-green figured velvet, the shining brass, silver, and glass, the wood that gleamed as darkly brilliant as the surface of a pool of oil. At one end a bronze figure sturdily held a support for a separated chamber, and at convenient places on the ceiling were frescoes in olive and silver.

At the beginning of the trip, Jack is chatty, but as they approach the town, he becomes more introspective as he considers how his constituents will react to his marriage.
Once they are back in Yellow Sky, Jack hurries his new wife through the back streets to his home, trying not to meet any of the townspeople along the way. He has an air of self-importance which causes him to worry about how he will tell the townsfolk he is a married man. He has an image as the marshal to protect. When he approaches his house, the opportunity to see how the people will react presents itself. The town troublemaker, Scratchy Wilson, appears at his door looking for a gun fight. Knowing he has to keep up appearances and control, Jack deals with Scratchy by telling him he is unarmed because he is returning home with his bride. While talking to Scratchy, Jack reverts to the language he uses when dealing with men.

His enemy's face went livid. He stepped forward and lashed his weapon to and fro before Potter's chest. "Don't you tell me you ain't got no gun on you, you whelp. Don't tell me no lie like that. There ain't a man in Texas ever seen you without no gun. Don't take me for no kid." His eyes blazed with light, and his throat worked like a pump.

Jack stays levelheaded as he deals with Scratchy, who is dumbfounded by the fact Jack Potter is a married man. That changes everything.