The difference between the old covenant of law and the new covenant of grace is like the difference between being a servant and being a son (or daughter) of the family. Servants can retain their position only for so long as they obey the rules; but children belong to their family by right of birth, and will never leave it. And it is the children, not the servants, who can address God as ‘Father’ (verses 6,7) and who will inherit all His blessings (verse 30).
All religions are a form of slavery – even Judaism (for although the Law is basically good, the devil has twisted it to serve his own evil purposes, so that it tyrannises and condemns those who try to keep it). But at least the Jews could look forward to a time when the Law would no longer be necessary (Luke 10:23,24). And that time finally came when the Son of God entered human history, incarnated (as God had promised – Genesis 3:15) in the womb of a woman (verse 4). Because He was born of a Jewish woman and circumcised when he was 8 days old, He put Himself under the yoke of the Law and bore it on our behalf. And because He obeyed the Law completely, He released us from that obligation and set us free forever from its power.
Gentile unbelievers are also in servitude: not to the Jewish Law (which never applied to them) but to idolatry and superstition (verse 8). The idea that God’s favour must be bought by doing good or by performing certain rituals is fundamental to man-made religion, and is very hard to shake off. It is therefore all too common for Christians from such a background to continue (or revert to) living in these old habits, serving God through fear rather than through love. Thus Christianity becomes perverted into a dreary formalism, dominated by rules and regulations (such as a strict liturgical calendar or a very narrow definition of Christian behaviour). This is not what the Christian life should be like!
So, do you act like a servant or a son? Do you think that you have to be continually earning God’s favour, or do you simply rejoice in it with gratitude? Are you confident in your relationship with God? You should be!