I found the following in Collected Christian Convictions, by Don Nash:

In answer to an atheist who had mailed him some infidel literature attacking the Christian faith, one preacher wrote the following rebuttal:

“My dear sir, if you have anything better than the Sermon on the Mount, the stories of the Prodigal Son and the Good Samaritan; or if you have a better moral code than the Ten Commandments; or if you can suggest anything more consoling and beautiful than the Twenty-third Psalm; or if you can supply anything that will throw more light on the future and reveal to me a Father more merciful and kind than the New Testament does; more meaningful than John 3:16, please send it to me.”

There was no reply.