When Christiana and her group visit the Interpreter's House, the Interpreter uses the simile of a hen and her chickens to show how Christ "calls" people to himself:
Now said he, compare this Hen to your King, and these Chickens to his obedient ones. For answerable to her, himself has his methods which he walketh in towards his People; by his common call he gives nothing; by his special call he always has something to give; he has also a brooding voice for them that are under his wing; and he has an outcry to give the alarm when he seeth the Enemy come. I chose, my Darlings, to lead you into the Room where such things are, because you are Women, and they are easy for you.
The Interpreter points out to Christiana that the hen uses different clucks and calls to communicate with her chicks, suggesting that God uses different means to communicate with different people. "Answerable to," or "like" a hen, Christ has specific methods for specific situations. By differentiating between Christ's "common" and "special" calls, the Interpreter refers to the theological concept of effectual calling, which basically means that not every person who hears God's teaching will respond to it, but that those who are specifically chosen by him will always both hear and respond—like a chick that knows its mother's familiar "cluck." Christ has a "brooding," or maternal, voice for those who are safely gathered "under his wing" (or within the Christian church) and a warning "outcry" for those in danger (vulnerable to Satan's attack). Overall, the simile suggests that those who belong to Christ will always recognize his voice.
It's also interesting that the Interpreter uses this simile for the women pilgrims because he says such homely images are "easy" for them. On one hand, his reasoning downplays women's intelligence. On the other hand, the whimsy of the image (a clucking chicken) obscures the sophistication behind theological ideas like effectual calling, which Bunyan clearly thought both male and female pilgrims ought to know and understand.