It is spring 1620 in Zurich, and the entire German world is in turmoil. War between the Catholic Hapsburgs, the traditional enemy of the Swiss, and the German Protestant states is about to break out. The young man Joggli (Jacob) is in town to pay family taxes in kind. He is fascinated by the appeal of a recruiter, and he signs up to go off to protect the newly crowned Protestant king in Prague. His trip, which ends in ignominious defeat at the battle of White Mountain in early winter, nearly costs him his life. And when he finally is one of the very few to make it back home, his family denounces him as a sinner for giving an oath to a sovereign power.

To win salvation, Joggli must repent, study the Scriptures, and get adult baptism to enter into the faith. But the reformed church in Zurich condemns him as a heretic Anabaptist and calls him to recant and threatens him with imprisonment, expulsion, or even execution unless he repents. Joggli keeps to his faith and even preaches it among his neighbors. He is thrown into prison, and his children are taken from him and distributed to reformed families. And he, with other Brethren, languish and suffer for several years in a dank, unheated prison in Zurich, constantly threatened with death and hunger. His faith holds firm and enables him to survive, until finally, the Zurich authorities expel all the Swiss Brethren from the canton. Released and able to collect his family, he begins his second large trip, this time leading a large collective of the Brethren out of Switzerland and into permanent exile in Alsace, a land desolated by the Thirty Years' War. Through prayer and study, they persevere and multiply and give thanks to Jesus, their Savior.