In the OP GIA quotes a bible verse which states:
Psalm 49:7 None of them can by any means redeem his brother,nor give to God a ransom for him.
GIA is hinting that nothing can be given for redemption, for example, Christ.
But if you read more of this verse it takes on a different meaning:
Psalm 49:6 those who trust in their wealth and boast of their great riches? 7 No one can redeem the life of another or give to God a ransom for them.
This verse clearly is talking about earthly wealth and how it means nothing to God. GIA clearly left out an integral part of the verse in order to distort the meaning.
Later someone posted this verse:
Ephesians 5:2 And walk in love, as Christ also hath loved us, and hath given himself for us an offering and a sacrifice to God for a sweetsmelling savour.
This was in an effort to prove that the "sacrifice" made by Jesus was the same as a human sacrifice. But it isn't if you look further in the bible.
Here is Jesus's words on the matter in John 15.13:Greater love has no one than this,that he lay down his life for his friends.
Here again in Mark 10.45:For even the Son of Man did not come to be served,but to serve,and to give his life as a ransom for many."
In other words Jesus sacrificed Himself for mankind. Not the same as blood sacrifices held during those times because they were a regular ritual as shown here:
Hebrews 7.27: Unlike the other high priests,he does not need to offer sacrifices day after day,first for his own sins,and then for the sins of the people. He sacrificed for their sins once for all when he offered himself.
There are two passages in the Jewish intertestamental literature that illustrate how two martyrs were understood this way:
4 Macc 6:26-28: "When he was now burned to his very bones and about to expire,he lifted up his eyes to God and said,27 "You know,O God,that though I might have saved myself,I am dying in burning torments for the sake of the law. 28 Be merciful to your people,and let our punishment suffice for them. 29 Make my blood their purification, and take my life in exchange for theirs."
4 Macc 17.20-22: "These,then,who have been consecrated for the sake of God,are honored,not only with this honor,but also by the fact that because of them our enemies did not rule over our nation,21 the tyrant was punished,and the homeland purified-they having become,as it were, a ransom for the sin of our nation. 22 And through the blood of those devout ones and their death as an atoning sacrifice,divine Providence preserved Israel that previously had been mistreated."
So,the understanding developed above is in line with the Jewish thought patterns of the period. Sacrificing one's self is not the same as blood sacrifices and was not considered immoral. Self sacrifice still isn't considered immoral. If a soldier throws himself on a grenade in order to save his platoon he is considered a hero, not immoral.
The reason I have a problem with the premise of this thread is because I have visited ruins of ancient societies that actually had human sacrifices. I have seen where they were held. There is usually an alter and it is understood to be a regularly held ritual. My disagreement of GIA's premise isn't just based on Christian bible text but also Jewish text and my own experiences of things I have seen for myself. The death of Jesus was a sacrifice but not a human sacrifice in the way some try to portray it.
So how moral and ethical is it to mis-represent a text in order question a religion....