Jacob Martini (1570-1649) was a prominent Lutheran theologian and philosopher during the late 16th and early 17th centuries. Born in Halberstadt, Germany, Martini played a significant role in the development of Lutheran Orthodoxy during a period marked by theological and philosophical challenges to the Reformation's legacy. He studied at the University of Wittenberg, the epicenter of Lutheran thought, where he would later teach and become one of its key figures. This book, Lutheranismus [Lutheranism] (1619), was structured on the pattern of Martin Luther's Small Catechism. and was structured to counter the many Calvinist claims which run counter to the biblical doctrine. It remains a useful model of Lutheran catechesis and apologetics, explaining the biblical foundation of many faithful practices of the Church of the Augsburg Confession.