Worshiping Jesus in the Mosque
Christianity Today looks at muslim background believers who stay within their Islamic culture while affirming that Jesus is Lord.
UPDATE:
A critique of the Insider Movement approach and a response.
This month's Evangelical Missions Quarterly examines the issue. Subscription required.
Two books on the question of Insider Movements and syncretism.
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"A Theological Analysis of the Insider Movement Paradigm from Four Perspectives: Theology of Religions, Revelation, Soteriology and Ecclesiology" (Doug Coleman)