I’m not sure what you mean; but the people back then thought very differently than we do today.
Pictorial Symbol was very important - most people couldn’t read. They ‘learned’ important concepts from paintings like this, and from all the other paintings, statuary - even the architecture itself - of the churches.
I think the original Lamb, as re-discovered in this painting, is very beautiful.
Absolutely.
Most people from the Middle Ages would have no trouble understanding why Van Eyck painted that lamb as he originally did. The Lamb of God might not be comprehended - nor found acceptable - by them if presented simply as a realistic lamb from a contemporary Flemish barnyard.
It took the high-priced smarties of the Renaissance to "reeducate" us.