The Liver and Onion Parable
Let me try and analogy on you, let's call it the Liver and Onion (LnO) Parable.
Suppose you detest LnO. The sight and smell make you sick. You once, to appease the insistence of a friend that LnO really is good tasting, touched your tongue's tip to the LnO and the taste repulsed you.
You are invited to a buffet where a friend suggests you try some LnO. You refuse. He insists that the LnO is wonderful. He takes a bite and smiles saying "Just try it." You say, "No way!"
You freely reject the LnO because of your senses (sight, taste and smell). You do so on this occasion and every occasion it is offered to you. Your action regarding LnO is predictable and certain.
SUCH is the unregenerate's free rejection of God because his heart and nature is only evil continuously.
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Now suppose this LnO loather is supernaturally change into a LnO lover.
God changes his taste buds as well as olfactory and mental responses. Now, at the buffet he asks his friend, "What smells so good?" He is surprised to find that the great smell comes from a plate of LnO! He is further surprised that it really doesn't look that bad now, in fact it looks good. He is salivating.
He grabs a fork and timidly takes a small bite to his tongue for a test. The test becomes a taste -- then he eats a huge serving. LnO has sudedenly become his favorite food. From that day on he looks for LnO whereever he can find it and he specifically requests it. He is a L&O lover now.
He freely and predictably chooses LnO after this craving has been placed upon him by God.
SUCH is the response of one who is regenerated by receiving a new heart and nature.
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BTW, in Heaven... Everyone loves LnO. Nothing else is eaten or even desired. All freely savor the smell and taste of LnO forever and ever. Hallelujah!