Thomas Paine. You should know who he is, but if you don’t, Wikipedia is your friend. Here’s a quote about the Christian doctrine of redemption, from The Age of Reason, his final book and the one that destroyed his reputation for good:
Since, then, no external evidence can, at this long distance of time, be produced to prove whether the church fabricated the doctrine called redemption or not, (for such evidence, whether for or against, would be subject to the same suspicion of being fabricated,) the case can only be referred to the internal evidence which the thing carries of itself; and this affords a very strong presumption of its being a fabrication. For the internal evidence is, that the theory or doctrine of redemption has for its basis an idea of pecuniary justice, and not that of moral justice.
If I owe a person money, and cannot pay him, and he threatens to put me in prison, another person can take the debt upon himself, and pay it for me. But if I have committed a crime, every circumstance of the case is changed. Moral justice cannot take the innocent for the guilty even if the innocent would offer itself. To suppose justice to do this, is to destroy the principle of its existence, which is the thing itself. It is then no longer justice. It is indiscriminate revenge.
I quote that mainly because I’ve been meaning to write something similar. Similar in content, that is. Paine’s prose is one of the reasons we’re a free country; it’s a tall order to write as well as he did.