Various ministry approaches have been utilized in Muslim nations in the past in order to lead lost souls into God's Kingdom. One noticeable trend in recent years in the ministry is an increasing emphasis on contextualization. While the evangelical missiological community searches for more effective contextualization models, some ad hoc proposals have complicated the issue. One representative case is the Insider Movement among Muslims, whose advocates contend that Muslim followers of Isa (Jesus) can remain within their own Islamic socio-religious community while continuing in Islamic religious practices. What is urgently needed in the contemporary discussion on contextualization is to develop a comprehensive analytical framework based on a sound biblical-theological foundation for evaluating any missiological model. After reviewing the historical development of Muslim evangelism models, this study provides such an analytical framework for developing a healthier contextualization model among Muslims and applies this framework to the Insider Movement by critically evaluating the biblical interpretations and missiological reasonings of the Insider Movement advocates. The writer calls for a healthier contextualization model among Muslims that is biblically authentic and culturally relevant. ""Daring, comprehensive, and profoundly biblical Mr. Hwang tackles the controversy surrounding Contextualization and the Insider Movement and their practical implications in ministry to Muslims. His historical background helps the reader understand the way the undergirding concepts have developed and provides a reasoned analysis and critique in light of the scriptures. This work is a step in the right direction as the missionary community tries to find 'healthier' approaches to culture and missions."" --Georges Houssney, President, Horizons International ""Wonjoo Hwang has written thoughtful critiques of many areas of Insider Movements and presents a better way forward. People should listen to him in being more critical--and above all, biblical--in our contextualization of the message, messengers and churches we establish overseas."" --Joshua Lingel, President, i2 Ministries; Biola Univeristy & Talbot School of Theology Wonjoo Hwang is Professor of the Bible at Petrescue Bible Institute in North Africa since 2015. After serving in one Islamic country for ten years, he studied the biblical-theological foundation for ministries to Muslim nations. He returned to the region for equipping national leaders in North Africa and Middle East. He is a co-editor for Journal of Arab and Islamic World Studies, and a contributor to Korea Missions Quarterly.