Chance is taking the chance of being killed in returning to St. Cloud. After getting Heavenly pregnant, he was threatened that if he ever returned to St. Cloud he would be castrated by Heavenly's father and brother. Chance is again warned by Scudder in the first scene of the play.
Scudder also warns Chance that he had better leave town before Heavenly’s father and brother come after him.
This threat of violence hangs over Chance throughout the play as he pursues contact with Heavenly. The longer Chance stays in St. Cloud, the more likely it becomes that he will be caught and castrated.
The reason this threat has been made against him is that Chance gave Heavenly a venereal disease that ruined her chances of ever having children.
Scudder is not the only character to warn Chance about the real threat of castration. The urgency of these warnings increase as the play goes on, leading to Chance's final flight in fear at the close of the play.