If God dictated the Bible, He can also dictate an interpretation to each and every one of us. The authors' cultural milieu is no more significant than our own. The message is what He speaks to us, just as He spoke it to them. The words are secondary.
Oh, well, in that case we can interpret it any way we please, such as what follows.
Mat 26:26 And as they were eating, Jesus took bread, and blessed [it], and brake [it], and gave [it] to the disciples, and said, Take, eat; this is my body.
Mat 26:27 And he took the cup, and gave thanks, and gave [it] to them, saying, Drink ye all of it;
Mat 26:28 For this is my blood of the new testament, which is shed for many for the remission of sins.
So if we adopt the interpretive philosophy outlined by you above, we might say something like this:
In the old days, they interpreted this passage as meaning that Jesus is going to die as payment for our sins. But God is giving me another message here, different from that old message. In this scene, we are symbolically eating God. Now what does this mean?
It means that God is getting inside of us and becoming a part of us, just as the potatoes we eat become a part of us. In the same way, the body and blood of Christ become us. Or another way of putting it is to say that we are becoming God. Through our various scientific advances, we can move things around real fast, and heat things up and cool things off real fast, and make complicated things out of many simple ingredients, and cure some diseases. In that way, we are becoming more and more Godlike. We are performing miracles. If we keep eating God, we will be able to do all of manner of things just as God does. God wants us to do this.
As regards that last bit about shedding the blood for the remissions of the sins of many, the new way of thinking of this is not that it is a propitiation. Notice that word "remission." If our taxes are remitted, it means we don't have to pay them. And so, in effect, we never had any taxes to begin with. Such is the meaning here. We never had any sins to begin with. What Jesus is saying is that this old idea that God expects payment for "sins" is nonsense. It's not a propitiation; it's an explanation of the new modern philosophy. The remission is that of the IDEA of sin, not sin per se. It is the "blood of the New Testament" that is being remitted--in other words, all those ancient ideas such as propitiation that were believed by the people who lived during the writing of the New Testament are hereby remitted.
That will do as well as another.
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