GRACE Galatians 3:17-18

What I mean is this: The law, introduced 430 years later, does not set aside the covenant previously established by God and thus do away with the promise. For if the inheritance depends on the law, then it no longer depends on the promise; but God in his grace gave it to Abraham through a promise.

The law, introduced 430 years later 
Genesis 15:13-14  Then the LORD said to him, "Know for certain that for four hundred years your descendants will be strangers in a country not their own and that they will be enslaved and mistreated there. But I will punish the nation they serve as slaves, and afterward they will come out with great possessions."
Exodus 12:40-42  Now the length of the time the Israelite people lived in Egypt was 430 years. At the end of the 430 years, to the very day, all the LORD's divisions left Egypt. Because the LORD kept vigil that night to bring them out of Egypt, on this night all the Israelites are to keep vigil to honor the LORD for the generations to come.
Acts 7:6-7  "God spoke to him in this way: 'For four hundred years your descendants will be strangers in a country not their own, and they will be enslaved and mistreated. But I will punish the nation they serve as slaves,' God said, 'and afterward they will come out of that country and worship me in this place.' "

For if the inheritance depends on the law, then it no longer depends on the promise 
Romans 4:14-16  For if those who depend on the law are heirs, faith means nothing and the promise is worthless, because the law brings wrath. And where there is no law there is no transgression. Therefore, the promise comes by faith, so that it may be by grace and may be guaranteed to all Abraham's offspring--not only to those who are of the law but also to those who have the faith of Abraham. He is the father of us all.

Scriptures taken from the Holy Bible, New International Version® NIV®, Copyright© 1973, 1978, 1984, 2011 by Biblica, Inc.® Used by permission. All rights reserved worldwide. 
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