Is feigning neutrality a good strategy in telling a nonbeliever about Jesus? In his Apologetics to the Glory of God, John Frame argues that doing so is not only unwise but dishonest.
To tell an unbeliever that we can reason with him on a neutral basis, however that claim might help to attract his attention, is a lie. Indeed, it is a lie of the most serious kind, for it falsifies the very heart of the gospel—that Jesus Christ is Lord. For one thing, there is no neutrality. Our witness is either God’s wisdom or the world’s foolishness. There is nothing in between. For another thing, even if neutrality were possible, that route would be forbidden to us. (7)
For one of the best popular efforts to do what Frame says we should do instead of attempting neutrality, see Tim Keller’s The Reason for God.