Gal.4: Now I say, That the heir, as long as he is a child, differeth nothing from a servant, though he be lord of all;
 But is under tutors and governors until the time appointed of the father.
 Even so we, when we were children, were in bondage under the elements of the world:
The tutors and governors represent the law. In the times of the law, a father had little to know dealings with his son until he reached the age of Bar Mitzvah. At the age of 13 the cild became an adult. This enabled him to begin his study of the law as directed by his father. Also, Jewish teaching is this became an age of responsibility before God for keeping the law. It also enabled the son to participate in prayer services and singing of the songs.
There is a deeper intimacy with God now. No longer dealing with us as children through tutors and governors but directly in a daily walk with Him through the Spirit. Having been born of the Spirit and circumcised internally.
 But when the fulness of the time was come, God sent forth his Son, made of a woman, made under the law,
 To redeem them that were under the law, that we might receive the adoption of sons.
 And because ye are sons, God hath sent forth the Spirit of his Son into your hearts, crying, Abba, Father.
 Wherefore thou art no more a servant, but a son; and if a son, then an heir of God through Christ.
Son as opposed to child (vs. 1). The sons of God in the Old Testament were angelic beings. The children of God were the Israelites. Having paid the atonement for the sins which had been covered by the blood of the old covenant and now having given us (Gentiles) the new birth by the Holy Spirit whereby we are now made sons of God.
1John.3: Behold, what manner of love the Father hath bestowed upon us, that we should be called the sons of God: therefore the world knoweth us not, because it knew him not.
 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.
Ro 8: Therefore, brethren, we are debtors, not to the flesh, to live after the flesh.
 For if ye live after the flesh, ye shall die: but if ye through the Spirit do mortify the deeds of the body, ye shall live.
 For as many as are led by the Spirit of God, they are the sons of God.
 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.
 The Spirit itself beareth witness with our spirit, that we are the children of God:
 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.
 Howbeit then, when ye knew not God, ye did service unto them which by nature are no gods.
 But now, after that ye have known God, or rather are known of God, how turn ye again to the weak and beggarly elements, whereunto ye desire again to be in bondage?
 Ye observe days, and months, and times, and years.
 I am afraid of you, lest I have bestowed upon you labour in vain.
Why would we after receiving sonship have a desire to engage in the Old Covenant? Paul after winning them to the Lord and bestowing much effort in teaching them the way of the New Testament would have been spinning his wheels if they were to revert to the Old Testament.
 Brethren, I beseech you, be as I am; for I am as ye are: ye have not injured me at all.
 Ye know how through infirmity of the flesh I preached the gospel unto you at the first.
 And my temptation which was in my flesh ye despised not, nor rejected; but received me as an angel of God, even as Christ Jesus.
 Where is then the blessedness ye spake of? for I bear you record, that, if it had been possible, ye would have plucked out your own eyes, and have given them to me.
 Am I therefore become your enemy, because I tell you the truth?
 They zealously affect you, but not well; yea, they would exclude you, that ye might affect them.
 But it is good to be zealously affected always in a good thing, and not only when I am present with you.
We are in this together. We are in the same boat. When he presented the gospel to them they received him and accepted him regardless of physical imperfections. They not only received him but would have done anything for him so great was the blessing they received. Now he is chastising them and they should continue to listen to him because he is giving them the Word of God still. Those that wanted to impose circumcision on them were not doing it for the benefit of the Galatians but for their own. Even as they had received Paul in the beginning they should continue in the same teaching. It was good for them at the beginning and continues to be for their good.
 My little children, of whom I travail in birth again until Christ be formed in you,
 I desire to be present with you now, and to change my voice; for I stand in doubt of you.
Paul having to explain again the simplicity in Christ and the freedom given to those of us who have accepted through faith, Jesus. The day to day walk of each of us is with one result in view and that is to be more like Christ each and every day.
 Tell me, ye that desire to be under the law, do ye not hear the law?
 For it is written, that Abraham had two sons, the one by a bondmaid, the other by a freewoman.
 But he who was of the bondwoman was born after the flesh; but he of the freewoman was by promise.
 Which things are an allegory: for these are the two covenants; the one from the mount Sinai, which gendereth to bondage, which is Agar.
 For this Agar is mount Sinai in Arabia, and answereth to Jerusalem which now is, and is in bondage with her children.
 But Jerusalem which is above is free, which is the mother of us all.
 For it is written, Rejoice, thou barren that bearest not; break forth and cry, thou that travailest not: for the desolate hath many more children than she which hath an husband.
 Now we, brethren, as Isaac was, are the children of promise.
 But as then he that was born after the flesh persecuted him that was born after the Spirit, even so it is now.
 Nevertheless what saith the scripture? Cast out the bondwoman and her son: for the son of the bondwoman shall not be heir with the son of the freewoman.
 So then, brethren, we are not children of the bondwoman, but of the free.
In the story of Abraham he and Sarah took it upon themselves to “help” God give Abraham a seed by Just as Abraham had two sons one bond and one of promise so there are two covenants. The Old Testament and the New. The Old Testament given on Mount Sinai was on of bondage with many do’s and don’ts. But the covenant from Heavenly Jerusalem is one of freedom and liberty. We are born of the Heavenly Jerusalem and not of the earthly Jerusalem.
Abraham having a child through Sarah’s handmaiden. Hagar was a bondservant. Ishmael born of the bondwoman gave trouble to Isaac. (Even to this day). Now those born of earthly Jerusalem persecute those of us born of the Heavenly Jerusalem.
The earthly Jerusalem is the home of the Jews but we are born of the Heavenly Jerusalem.
Under the Old Covenant Israel was married to the Lord. However many saints she bore there will be more in this current dispensation. (Isaiah 54:1-8)
Revelation 21: And I saw a new heaven and a new earth: for the first heaven and the first earth were passed away; and there was no more sea.
 And I John saw the holy city, new Jerusalem, coming down from God out of heaven, prepared as a bride adorned for her husband.
Hebrews 11: By faith Abraham, when he was called to go out into a place which he should after receive for an inheritance, obeyed; and he went out, not knowing whither he went.
 By faith he sojourned in the land of promise, as in a strange country, dwelling in tabernacles with Isaac and Jacob, the heirs with him of the same promise:
 For he looked for a city which hath foundations, whose builder and maker is God.
Hebrews 12:22] But ye are come unto mount Sion, and unto the city of the living God, the heavenly Jerusalem, and to an innumerable company of angels,
 To the general assembly and church of the firstborn, which are written in heaven, and to God the Judge of all, and to the spirits of just men made perfect,
 And to Jesus the mediator of the new covenant, and to the blood of sprinkling, that speaketh better things than that of Abel.