Thats a pretty vague statement. Changed peoples thinking and lives how? By loving God and our neighbors? And if we love our neighbors do we not wish for their eternal salvation? And if we wish for their eternal salvation shouldn't we wish for all our neighbors to accept Christ as their Lord? Since Christ explicitly stated that the only path to salvation was through Him, and since he explicitly ordered us to love one another, how can one say they love someone, but they 'can't be bothered' to worry about their salvation. Since Christ came to us specifically for our salvation, how uninterested could He possible have been when it was what He preached?
Changing lives and thinking is great, if done in the name of the Lord. In order to accept Christ as lord one has to believe.