There are two radical differences between Humanism and Christianity.
Christianity concerns itself with God and Man, putting God first and Man last.
Humanism concerns itself solely with Man, so that Man is its first and last care. That is one radical difference.
Then, Christianity accepts the doctrine of Free Will, with its consequent rewards and punishments; while Humanism embraces Determinist doctrines, with their consequent theories of brotherhood and prevention. And that is another radical difference.
Because the Christian regards the hooligan, the thief, the wanton, and the drunkard as men and women who have done wrong. But the Humanist regards them as men and women who have been wronged.
The Christian remedy is to punish crime and to preach repentance and salvation to "sinners." The Humanist remedy is to remove the causes which lead or drive men into crime, and so to prevent the manufacture of "sinners."
Let us consider the first difference. Christianity concerns itself with the relations of Man to God, as well as with the relations between man and man. It concerns itself with the future life as well as with the present life.
Now, he who serves two causes cannot serve each or both of them as well as he could serve either of them alone.
He who serves God and Man will not serve Man as effectually as he who gives himself wholly to the service of Man.
As the religion of Humanism concerns itself solely with the good of humanity, I claim that it is more beneficial to humanity than is the Christian religion, which divides its service and love between Man and God.