Zacharius Ursinus, German theologian (died 1583)

Zacharias Ursinus was a German Reformed theologian and Protestant reformer. He became the leading theologian of the Reformed Protestant movement of the Palatinate, serving both at the University of Heidelberg and the College of Wisdom. He is best known as the principal author and interpreter of the Heidelberg Catechism.

July 18 is the 199th day of the year in the Gregorian calendar; 166 days remain until the end of the year.