Martin Luther, Augustine, Thomas Aquinas, Calvin, Wesley - all great men. Billy Graham, Packer, Piper, Warren or some other popular preacher of today, all might be considered great men. Then there's John the Baptist, who Jesus considered the greatest of all, and yet, according to Jesus, the least in the kingdom of heaven, is greater than any of them, not because they weren't or are not great, but because we have little comprehension of the great perfection of heaven or the great sinfulness of man. We should still strive to do our best and to honor God and if we become "great" in the eyes of man, so be it. Just remember though, until we get to heaven, we're not really great yet - but He is.

Matthew 11:11