Galatians 4:1-4
I mean that the heir, as long as he is a child, is no different from a slave, though he is the owner of everything, 2 but he is under guardians and managers until the date set by his father. 3 In the same way we also, when we were children, were enslaved to the elementary principles of the world.
Does Galatians 4 tell us that the elect were already sons of God even while they were enslaved to the elementary principles of the world?
No. Galatians 4 does not say we were always children of God. How could it say this, when the same Paul, writing by the same Spirit, says in Romans 8:10 that if we have not the Spirit of Christ then we are none of His?
What Paul is doing in Galatians 4 is analogizing the relationship of an heir to a slave in order to draw a comparison between the elect and the law. In other words, an heir is to a slave as the elect are to the law. So, when he says, “Even so, when we were children . . .” he’s using the word children in the context of his analogy.
To put it another way; a cub is to a bear as a baby is to a human; therefore, when we are cubs we are at the mercy of our mother.
Am I telling you that I believe we begin life as bear cubs? No, course not. Instead, I am using the language of the analogy I created in order to make a point.
In regards to Galatians 4, the Good News Translation brings this out much more clearly than the KJV or the ESV does.
GNT:But now to continue—the son who will receive his father’s property is treated just like a slave while he is young, even though he really owns everything. 2 While he is young, there are men who take care of him and manage his affairs until the time set by his father. 3 In the same way, we too were slaves of the ruling spirits of the universe before we reached spiritual maturity. 4 But when the right time finally came, God sent his own Son. He came as the son of a human mother and lived under the Jewish Law, 5 to redeem those who were under the Law, so that we might become God’s children.
Cornbread & Bourbon 
Just like a child is not a son/daughter is not a son/daughter until born as a human, the elect is not a son/daughter Until born again or from above.
A sheep is always a sheep. A sheep is not always justified before God. Christ was and is always elect. But at one time Christ (God the Son) died under the law and guilt wrath of God the Trinity. Christ by His propitiation obtained righteousness. Galatians 3, Galatians 4—sons of Abraham. Not all children of Abraham are children of Abraham. Not all children of Abraham are chosen by God to pass from death to lasting life. Galatians 3: 22 The promise through faith in Jesus Christ is given to those who believe. 23 Before the object of faith came, all physical children of Abraham (justified or not justified) were confined under the law, IMPRISONED until the OBJECT OF faith was revealed
Paul the Jew, Galatians 4: 3 When we were children, WERE IN SLAVERY under the elemental forces of the world. 4 When the TIME CAME, God sent His Son, born of a woman, BORN UNDER THE LAW
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