In Christ a new kind of man appeared: and the new kind of life which began in Him is to be put into us.
How is this to be done? Now, please remember how we acquired the old, ordinary kind of life. We derived it from others, from our father and mother and all our ancestors, without our consent - and by a very curious process, involving pleasure, pain, and danger. A process you would never have guessed. Most of us spend a good many years in childhood trying to guess it: and some children, when they are first told, do not believe it - and I am not sure that I blame them, for it is very odd. Now the God who arranged that process is the same God who arranges how the new kind of life - the Christ-life - is to be spread. We must be prepared for it being odd too. He did not consult us when He invented sex: He has not consulted us either when He invented this.
There are three things that spread the Christ-life to us: baptism, belief, and that mysterious action which different Christians call by different names - Holy Communion, the Mass, the Lord's Supper. At least, those are the three ordinary methods...
I cannot myself see why these things should be the conductors of the new kind of life. But then, if one did not happen to know, I should never have seen any connection between a particular physical pleasure and the appearance of a new human being in the world. We have to take reality as it comes to us: there is no good jabbering about what it ought to be like or what we would have expected it to be like.