You are a child of your father means; You look like him in what you say and do.
This expression "child of" may apply to different sorts of behavior;
He is a child of the revolution.
He is a child of corruption.
He is a child of the seventies.
He is a child of his education.
It's what you say and do that defines you.
If you do as God would (want you to) do, you are a child of God.
The Spirit Himself bears witness with our spirit that we are the children of God. Ro 8:16 MKJV
And children grow up; a Son of God is one who is guided by the Spirit of God; peacemakers.
And all those who are guided by the Spirit of God are sons of God. Ro 8:14
Happy are the peacemakers: for they will be named sons of God. Mt 5:9
You become a mature son of God when you are raised from the dead; If at death your soul survives;
and not only the creation, but we ourselves, who have the first fruits of the Spirit, groan inwardly as we wait for adoption as sons, the redemption of our bodies. Ro 8:23
Those souls who died as true children of God will survive death even if their bodied have died.
And death has no more power over them, for they are equal to the angels, and are sons of God, being of those who will come back from the dead. Lu 20:36
Thanks to his achievements in his passed lives, Jesus was the first one (and at that time the only one) to be born a Son of God.
"I will be to him a father, and he shall be to me a son" Heb 1:5 (1Ch 22:10)
And that is how Jesus is a Son of God, and... he is not the only one....
Because those of whom he had knowledge before they came into existence, were marked out by him to be made like his Son, so that he might be the first among a band of brothers. Ro 8:29
God put Jesus in charge and it is Gods will that his children are witnesses of Jesus.
Whoever shall confess that Jesus is the Son of God, God dwelleth in him, and he in God. 1Jo 4:15
I said, You are gods; all of you are the sons of the Most High. Ps 82:6
Because you are all sons of God through faith in Christ Jesus. Ga 3:26BBEAnd I shall be a Father to them, and they will be sons to me. And they will all be called "sons of the living God". And every angel and spirit will know and acknowledge that they are my sons and I am their Father in uprightness and righteousness. Jubilees 1;25
And it came to pass that Moses looked upon Satan and said: Who art thou? For behold, I am a son of God, in the similitude of his Only Begotten; and where is thy glory, that I should worship thee? Mormon; Moses 1;13
Persons may be called sons of God, but the term may also apply to entire (root)races or soul-collectives;
As a son of God, Adam; the better part of mankind, has the potential of becoming a god;
Adam, Adam, do not fear. You wanted to be a god; I will make you a god, not right now, but after a space of many years. Test. Adam 3;2
Or elsewhere in space, creating a world of their own, as is written in the Testimony of Mary.
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Some (members) of these races (or soul-collectives) have fallen from their "thrones", rebelled and descended to Earth in the past in order to mix with Earthly women;
And after a time, when men were increasing on the earth, and had daughters, the sons of God saw that the daughters of men were fair; and they took wives for themselves from those who were pleasing to them. Gen 6;1
which led to their downfall; they became known as the "Fallen angels" or the fallen Watchers described in the books of Enoch.
Then the Lord said
to me: Enoch, scribe of righteousness, go tell the Watchers of heaven, who have
deserted the lofty sky, and their holy everlasting station, who have been
polluted with women, and have done as the sons of men do, by taking to
themselves wives, and who have been greatly corrupted on the earth, that on the
earth they shall never obtain peace and remission of sin, for they shall not
rejoice in their offspring; they shall behold the slaughter of their beloved;
shall lament for the destruction of their sons; and shall petition for ever; but
shall not obtain mercy and peace. 1Enoch 12,14