Frederick Antony Ravi Kumar Zacharias was an Indian-born Canadian-American Christian evangelical minister and Christian apologist who founded Ravi Zacharias International Ministries (RZIM). He was involved in Christian apologetics for a period spanning more than forty years, authoring more than thirty books. He also hosted the radio programs Let My People Think and Just Thinking. Zacharias belonged to the Christian and Missionary Alliance (C&MA), the Keswickian Christian denomination in which he was ordained as a minister.

Christian apologetics is a branch of Christian theology that defends Christianity.