The Serpent in Genesis 3 SERIES: What Was the Forbidden Fruit?

"In Genesis 3:2–3, Eve repeats God’s command about eating from the tree of knowledge: “We may eat of the fruit of the trees in the garden, but God said, ‘You shall not eat of the fruit of the tree that is in the midst of the garden, neither shall you touch it, lest you die.’”

In church tradition, the fruit has often been identified as an apple

probably because the Latin word malum, “apple,” sounds like the word malus, “evil.” 

However, Genesis does not tell us what the fruit (pǝrî, Genesis 1:11-12) was. The only fruit mentioned in the passage is the fig (Genesis 3:7).

The fact of the matter is that it is not that important to know what the fruit was. What is important is that by taking of the fruit both Adam and Eve sinned against God. Because of Adam’s disobedience, God drove him out of the garden so that he could not eat from the tree of life and live forever (Genesis 3:22–24)." 

AIG