Consider these sentences from Monstrous Regiment:

She’d never prayed since the day the bird burned, not even when her mother was dying. A god that burned painted birds would not save a mother. A god like that was not worth a prayer.

But Wazzer prayed for everyone. Wazzer prayed like a child, eyes screwed up and hands clenched until they were white. The reedy little voice trembled with such belief that Polly felt embarrassed, and then ashamed, and, finally, after the ringing “amen,” amazed that the world appeared no different than before. For a minute or two, it had
been a better place…

Polly’s complicated reaction to the way Wazzer prays characterizes her. It lets readers know why she reacts the way she does. Pratchett creates this contrast between the characters to reveal more about each of them, though because readers have access to Polly’s inner life they learn more about her. These seven sentences give two characters each a distinct way of looking at the world, a cosmology, and hint at the possibility that Polly might be changed by Wazzer’s, or that she is at least surprised by the power of it. The question of whether this contrast will lead to conflict or change is implied, and readers might read on wondering if this question will be answered. The different ways these characters look at the world is theological here but could be economic, sociological, etc.

Let one character observe another in a way that reveals contrasts between them and let that contrast imply big questions about their world and perhaps relationship.

See Charles Baxter’s “Counterpointed Characterization” in Burning Down the House for more about this technique.