The apostle Paul may have something to tell us about the ethics of evangelism. If eternal souls are at stake, is the "lesser evil" of deception not worth comitting in order to prevent the "greater evil" of an eternal suffering?
1 Cor. 9:19-24 (NIV)
19Though I am free and belong to no man, I make myself a slave to everyone, to win as many as possible. 20To the Jews I became like a Jew, to win the Jews. To those under the law I became like one under the law (though I myself am not under the law), so as to win those under the law. 21To those not having the law I became like one not having the law (though I am not free from God's law but am under Christ's law), so as to win those not having the law. 22To the weak I became weak, to win the weak. I have become all things to all men so that by all possible means I might save some. 23I do all this for the sake of the gospel, that I may share in its blessings. 24Do you not know that in a race all the runners run, but only one gets the prize? Run in such a way as to get the prize.
Is Paul saying here to misrepresent ones heritage and beliefs, if necessary, so that under false pretenses, more trust would be garnered, and more souls "won"? How much clearer does it get than "by all possible means"? A little clearer:
Phil 1:15-18 (NIV)
15It is true that some preach Christ out of envy and rivalry, but others out of goodwill. 16The latter do so in love, knowing that I am put here for the defense of the gospel. 17The former preach Christ out of selfish ambition, not sincerely, supposing that they can stir up trouble for me while I am in chains. 18But what does it matter? The important thing is that in every way, whether from false motives or true, Christ is preached. And because of this I rejoice. (emphasis mine)
Whether from pretense or transparency, the important thing is the Gospel. Pretty clear. The ends justify the means...at least, according to Paul here.