I will respond to the underlined statement by saying you surely cannot be serious.
There were only two men in the entire history of the church who were capable of dying spiritually. Both the men were called the son of God. The first one was the first man, a creation of God. He was created a trinity. And BTW, all things created by God has a trinitarian identity. All the angelic hosts and all redeemed humanity are called "sons of God" because they are special creations, except Jesus Christ who is the Son of God by a woman. He was not created, he was generated.
Mt 1:1 The book of the generation of Jesus Christ, the son of David, the son of Abraham.
All saved people becomes a "new" creation.
2Co 5:17 Therefore if any man be in Christ, he is a new creature: old things are passed away; behold, all things are become new.
He is not revamped, renovated, he is made new. In fact he is re "newed." Take a look;
Tit 3:5 Not by works of righteousness which we have done, but according to his mercy he saved us, by the washing of regeneration, and renewing of the Holy Ghost;
The renewing of the Holy Ghost is what makes him a new creature. How so you say. By making him a trinity, soul, body, and the indwelling Holy Ghost. This is the same Holy Ghost that Jesus Christ dismissed just as the world turned dark at 12 noon the day he was crucified.
Joh 1:4 In him was life; and the life was the light of men.
5 And the light shineth in darkness; and the darkness comprehended it not.
The wonderful thing about this gospel is that new creatures in Christ cannot be condemned by sinning because the righteousness of Jesus Christ is imputed unto us who believe and we can never be condemned by anything.
Ro 8:34 Who is he that condemneth? It is Christ that died, yea rather, that is risen again, who is even at the right hand of God, who also maketh intercession for us.
35 Who shall separate us from the love of Christ? shall tribulation, or distress, or persecution, or famine, or nakedness, or peril, or sword?
36 As it is written, For thy sake we are killed all the day long; we are accounted as sheep for the slaughter.
37 Nay, in all these things we are more than conquerors through him that loved us.
38 For I am persuaded, that neither death, nor life, nor angels, nor principalities, nor powers, nor things present, nor things to come,
39 Nor height, nor depth, nor any other creature, shall be able to separate us from the love of God, which is in Christ Jesus our Lord.
That is as secure as one can get.
So here are the only two men capable of dying spiritually and this will provide you with the verse you say is not in the scriptures.
Ga 4:4 But when the fulness of the time was come, God sent forth his Son, made of a woman, made under the law,
5 To redeem them that were under the law, that we might receive the adoption of sons.
6 And because ye are sons,
God hath sent forth the Spirit of his Son into your hearts, crying, Abba, Father.
Lu 3:38 Which was the son of Enos, which was the son of Seth, which was the son of Adam, which was the son of God.
These are the only two men who had the Spirit indwelling them as a member of their persons in all the OT. Both these men died spiritually, meaning the Spirit departed from them, and the Spirit departed both men for the same reason. Because of sin. One had sin in him and one had sin on him. This is spiritual death for both men. Spiritual death is defined by the departure of God the Spirit from the body while physical death is the departure of the soul from the body. Both were heads of families. Adam was the head of the unregenerate family and all his offspring are like him, body and soul.. Jesus Christ is the head of the family of God, a family of people born again into his family by the Spirit and who are all like Jesus, in the image of God, trinitarian. This is so because the Spirit indwells their bodies. We are predestined to have a body like his glorious body, the body of Jesus, an immortal body that can never sin and never die. This will be accomplished when this family is complete.
Php 3:20 For our conversation is in heaven; from whence also we look for the Saviour, the Lord Jesus Christ:
21 Who shall change our vile body, that it may be fashioned like unto his glorious body, according to the working whereby he is able even to subdue all things unto himself.
1Jo 3:2 Beloved, now are we the sons of God, and it doth not yet appear what we shall be: but we know that, when he shall appear, we shall be like him; for we shall see him as he is.
Now, here is your verse;
Ge 2:16 And the LORD God commanded the man, saying, Of every tree of the garden thou mayest freely eat:
Ge 2:17 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.
Anyone knows that Adam lived 930 years after the day he ate of the tree. So, what kind of death did Adam die in that day? He died spiritually. He had been in fellowship with God in the garden until then. After that there had to be an innocent lamb to cover his nakedness. It is not strange when man is reconciled to God and in fellowship with him when he receives the Spirit of God, who also makes him a son of God by his presence in his mortal body.
Rom 8:14 For as many as are led by the Spirit of God, they are the sons of God.
15 For ye have not received the spirit of bondage again to fear; but ye have received the Spirit of adoption, whereby we cry, Abba, Father.
16 The Spirit itself beareth witness with our spirit, that we are the children of God:
17 And if children, then heirs; heirs of God, and joint-heirs with Christ; if so be that we suffer with [him], that we may be also glorified together.
Jesus Christ had to die the death of a man and endure the wrath of God for us or we could never be children of God. It was the only way. to wash away our sins.
Re 1:5 And from Jesus Christ, who is the faithful witness, [and] the first begotten of the dead, and the prince of the kings of the earth. Unto him that loved us, and washed us from our sins in his own blood,
Heb 2:9 But we see Jesus, who was made a little lower than the angels for the suffering of death, crowned with glory and honour; that he by the grace of God should taste death for every man.
1 And can it be that I should gain
An int'rest in the Savior's blood?
Died He for me, who caused His pain?
For me, who Him to death pursued?
Amazing love! how can it be
That Thou, my God, should die for me?
Refrain:
Amazing love! how can it be
That Thou, my God, should die for me!
2 'Tis mystery all! Th'Immortal dies!
Who can explore His strange design?
In vain the firstborn seraph tries
To sound the depths of love divine!
'Tis mercy all! let earth adore,
Let angel minds inquire no more. [Refrain]
3 He left His Father's throne above,
So free, so infinite His grace;
Emptied Himself of all but love,
And bled for Adam's helpless race;
'Tis mercy all, immense and free;
For, O my God, it found out me. [Refrain]
4 Long my imprisoned spirit lay
Fast bound in sin and nature's night;
Thine eye diffused a quick'ning ray,
I woke, the dungeon flamed with light;
My chains fell off, my heart was free;
I rose, went forth and followed Thee. [Refrain]
5 No condemnation now I dread;
Jesus, and all in Him is mine!
Alive in Him, my living Head,
And clothed in righteousness divine,
Bold I approach th'eternal throne,
And claim the crown, through Christ my own. [Refrain]
Amen.
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