Romans 11  Paul, writing to Gentiles, explains what has happened to Israel.  God had not rejected the Jews altogether.  He has kept for Himself a "remnant according to God's gracious choice." (v5)
God has chosen some to obtain salvation through His grace, but others have been "hardened". (v7)

Paul argues that one reason for this is so that the Gentiles could come to salvation, making the Jews jealous.  If their failure/transgression is able to bring salvation to the world, then, Paul says, what will their "fulfillment" be?  If their rejection ( of Christ) allows the world to be reconciled to God, then what will their acceptance of Him bring? Paul says it will bring "life from the dead"! ( v15)

God is not through with Israel, Paul teaches.  They are the natural branches of the olive tree.
Those who have not believed in Christ are like branches that have been broken off.  The Gentile believers are like branches from a wild olive tree that have been grafted into the holy tree whose root is Christ. Two truths that we need to take note of here:
1.  The Lord is able to graft the broken branches back in again!
2.  The Lord will cut off even the grafted branches if they do not "continue in His kindness."

The mysterious and wonderful ways of God are beyond our understanding. He has allowed His people to reject His Son.. so that He could show mercy to all people.  He allowed disobedience for all so that He could reveal His mercy to all.  Paul writes, " Oh , the depth of the riches both of the wisdom and knowledge of God! How unsearchable are His judgements and unfathomable His ways." ( v33)

We cannot know God's mind.  We cannot see the greatness of His full purposes and will.  But, we can give Him glory and honor because, " from Him and through Him and to Him are all things." ( v36)

Father, we do give You glory and honor and praise.  For You are the source of all life.  You are the creator and sustainer of all the world, by Your choice and express purposes.  We are thankful for Your righteousness and mercy.  We thank You that all people have hope through Christ Jesus.  We thank You for calling us by name, for choosing us to be grafted onto the holy Vine.  We bow before You and humble ourselves, knowing that we did not earn this, but that it is Your gift by grace and we have it only by faith in our Precious Savior.  Teach us anew the wonder of Your salvation and the greatness of Your love.  May we never forget or take this for granted.  Amen.