Banner in the Sky is a coming-of-age story that shows Rudi’s progression as he learns that masculinity and maturity are defined not by might or appearance, but by courage and self-sacrifice. Rudi manages to overcome his insecurity and impulsiveness through the mentorship of other characters and his own experiences as a climber.

Rudi needs the mentorship of others to help him become a mature adult. His predicament shocks him when he gets into a potentially deadly situation, but Winter and Franz’s “experienced eyes told them what had happened” (69). Similarly, Old Teo chastises Rudi for his actions, saying that the trouble with youth is that “once you have learned a little, then you think that you know it all” (75). Teo reminds Rudi to watch and learn from others, and he learns from Winter’s courage and Franz’s caution. This is an irreplaceable part of Rudi’s growth, making him feel that he is “where he belonged. A man among men” (59). Winter’s confidence in and inclusion of Rudi provide the affirmation that he needs at a pivotal moment in his development. When Franz points out that the Citadel isn’t child’s play, Winter argues, “Rudi here is no child.