Christianity borrowed everything important from earlier religions.

Moral and religious overlap is exactly what Christianity predicts, not what it has to explain away. (1) C.S. Lewis (The Abolition of Man, Appendix; Mere Christianity) argues that the shared moral intuitions of humanity (the Tao) are evidence of a common moral reality, not evidence that Christianity is cobbled together. Romans 1-2 explicitly teaches that God has written moral law on the human heart and that pagans without the Jewish scriptures are still accountable to conscience. Of course Confucius recognized the Golden Rule - he was a human being with a conscience. (2) The Christian distinctive is not a novel ethical maxim; it is a person: a crucified Jewish carpenter who claimed authority to forgive sins, was vindicated by resurrection, and reconstitutes Israel around himself. That claim has no real parallel. Akhenaten's monotheism died with him; Hillel never claimed to be the Son of Man; Socrates did not rise from the dead. (3) Where Christianity did innovate - care for infants exposed on Roman hillsides, hospitals for the sick of any class, universal human dignity grounded in imago Dei, the equality of slave and free before God, the radical forgiveness of enemies - the innovations reshaped Western moral imagination so thoroughly that even post-Christian critics argue from values Christianity put into circulation (Larry Siedentop, Inventing the Individual; Tom Holland, Dominion; Nietzsche saw this with bitter clarity).