There must be some misunderstanding. There is no such teaching in the Bible about the cause of sin. James tells us what is the cause of sin (James 1:14,15): But every man is tempted, when he is drawn away of his own lust, and enticed. Then when lust hath conceived, it bringeth forth sin: and sin, when it is finished, bringeth forth death.
So here's how it works:
OUTWARD TEMPTATION-->INNER LUST TRIGGERED-->SIN PRODUCED (WORD OR ACTION)-->PENALTY = DEATH
There are three primary lusts, and Eve succumbed to all three:
THE LUST OF THE FLESH = And when the woman saw that the tree was good for food
THE LUST OF THE EYES = ...and that it was pleasant to the eyes
THE PRIDE OF LIFE = ... and a tree to be desired to make one wise
So here's how it works:
OUTWARD TEMPTATION-->INNER LUST TRIGGERED-->SIN PRODUCED (WORD OR ACTION)-->PENALTY = DEATH
There are three primary lusts, and Eve succumbed to all three:
THE LUST OF THE FLESH = And when the woman saw that the tree was good for food
THE LUST OF THE EYES = ...and that it was pleasant to the eyes
THE PRIDE OF LIFE = ... and a tree to be desired to make one wise