Isn't blood sacrifice the core principle of Christianity?
Yes, thus showing how immoral a religion it is.
Here is what I often tell them from their own bible.
On Jesus dying for you.
It takes quite an ego to think a god would actually die for you, after condemning you unjustly in the first place.
You have swallowed a lie and don’t care how evil you make Jesus to keep your feel good get out of hell free card.
It is a lie, first and foremost because, like it or not, having another innocent person suffer or die for the wrongs you have done, --- so that you might escape responsibility for having done them, --- is immoral. To abdicate your personal responsibility for your actions or use a scapegoat is immoral.
You also have to ignore what Jesus, as a Jewish Rabbi, would have taught his people.
Ezekiel 18:20 The soul that sinneth, it shall die. The son shall not bear the iniquity of the father, neither shall the father bear the iniquity of the son: the righteousness of the righteous shall be upon him, and the wickedness of the wicked shall be upon him.
Deuteronomy 24:16 (ESV) "Fathers shall not be put to death because of their children, nor shall children be put to death because of their fathers. Each one shall be put to death for his own sin.
Psa 49;7 None of them can by any means redeem his brother, nor give to God a ransom for him:
There is no way that you would teach your children to use a scapegoat to escape their just punishments and here you are doing just that.
Jesus is just a smidge less immoral than his demiurge genocidal father, and here you are trying to put him as low in moral fibre as Yahweh.
Christians tend to run away at this point as they know they cannot refute the logic shown.
Cowards can never be moral.