So why are we spiritually dead and blind? We inherit our spiritual deadness and blindness from our first ancestor, Adam.
1 Corinthians 15:45 And so it is written, The first man Adam was made a living soul; the last Adam was made a quickening spirit. 46 Howbeit that was not first which is spiritual, but that which is natural; and afterward that which is spiritual. 47 The first man is of the earth, earthy: the second man is the Lord from heaven. 48 As is the earthy, such are they also that are earthy: and as is the heavenly, such are they also that are heavenly. 49 And as we have borne the image of the earthy, we shall also bear the image of the heavenly. 50 Now this I say, brethren, that flesh and blood cannot inherit the kingdom of God; neither doth corruption inherit incorruption. 51 Behold, I shew you a mystery; We shall not all sleep, but we shall all be changed, 52 In a moment, in the twinkling of an eye, at the last trump: for the trumpet shall sound, and the dead shall be raised incorruptible, and we shall be changed. 53 For this corruptible must put on incorruption, and this mortal must put on immortality. 54 So when this corruptible shall have put on incorruption, and this mortal shall have put on immortality, then shall be brought to pass the saying that is written, Death is swallowed up in victory.
Genesis 2:16 And the LORD God commanded the man, saying, Of every tree of the garden thou mayest freely eat: 17 But of the tree of the knowledge of good and evil, thou shalt not eat of it: for in the day that thou eatest thereof thou shalt surely die.
Genesis 5:5 And all the days that Adam lived were nine hundred and thirty years: and he died.
Adam lived physically 930 years after eating the forbidden fruit. He died a different kind of death the day he ate the forbidden fruit. He died spiritually. Spiritual death is separation from God, the source spiritual life and the Creator of physical life.