Heermann was born in Raudten (modern day Rudna) in Silesia, the fourth son of a middle-class Protestant family.

In 1602, he moved to Fraustadt, where he lived and worked with the theologian Valerius Herberger, who employed him as amanuensis and tutor to his son Zacharias.

He decided to go to university in 1607, but was persuaded by his patron, Wenzel von Rothkirch, to stay with him, teaching his two sons and accompanying them on a trip around Europe.

Over Easter 1609 he travelled via Leipzig and Jena to Strasbourg, where they matriculated at the university, attending theology lectures and meeting the professors of rhetoric and law.

Soon after his return, he was ordained and appointed deacon to the Lutheran congregation in Köben (modern-day Chobienia, Poland), where the incumbent pastor was old and in poor health.

The effects of the Thirty Years' War struck soon afterwards, and Köben was plundered by Catholic troops in 1632, 1633, 1634 and 1642, and Heermann lost his worldly possessions several times.

Johann Sebastian Bach based his chorale cantata Wo soll ich fliehen hin, BWV 5 on Heermann's hymn with the same name.