Genesis 2:16-17 And the Lord God commanded the man, saying, Of every tree of the garden thou mayest freely eat: 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.

Since God cannot lie, what death did Adam die on the day Adam ate of the tree of knowledge of good and evil?

Genesis 3:23 Therefore the Lord God sent him forth from the garden of Eden, to till the ground from whence he was taken.

Being separated from God is spiritual death. That death came that day to Adam and Eve. It is that death that was forewarned. It is that death that reigned until a cure could be found. Man, with his desires of life only concerns himself with a physical death and every time man thinks about death or sees death, the only consideration he makes is of a physical death.

Romans 5:14, 17, 21 Nevertheless death reigned from Adam to Moses, even over them that had not sinned after the similitude of Adam’s transgression, who is the figure of him that was to come. For if by one man’s offence death reigned by one; much more they which receive abundance of grace and of the gift of righteousness shall reign in life by one, Jesus Christ. That as sin hath reigned unto death, even so might grace reign through righteousness unto eternal life by Jesus Christ our Lord.

Man, in the selfishness of his sin nature, only concerns himself with a physical death whereas God weeps over a death that led to separation from His creation.

Revelation 20:6 Blessed and holy is he that hath part in the first resurrection: on such the second death hath no power, but they shall be priests of God and of Christ, and shall reign with him a thousand years.

The second death is a permanent separation from God and should be our primary concern.