Long ago, God promised a new covenant of grace for His people Israel. Someday, all Israelites will turn to Messiah Jesus and realize they are recipients of His covenant of grace.
"And so all Israel will be saved, as it is written: The Deliverer will come out of Zion, and He will turn away ungodliness from Jacob; for this is My covenant with them, when I take away their sins." (Romans 11:26-27).
This will take place when the Lord Jesus returns to this earth.
"And I will pour on the house of David and on the inhabitants of Jerusalem the Spirit of grace and supplication; then they will look on Me whom they have pierced; they will mourn for Him as one mourns for his only son and grieve for Him as one grieves for a firstborn." (Zechariah 12:10).
Grace is not exclusive to Israel. The Grace of God has appeared to all humanity and brought them salvation.
"For the grace of God has appeared, bringing salvation to all humanity..."(Titus 2:11)
"Faithful is the saying and worthy of all welcome (for for this are we toiling and being reproached), that we rely on the living God, Who is the Savior of all humanity, especially of believers. These things be charging and teaching." (1 Timothy 4:9-10)
"God, being rich in mercy, because of His vast love with which He loves us (we also being dead to the offenses and the lusts), vivifies us together in Christ (in grace are you saved!) and rouses us together and seats us together among the celestials, in Christ Jesus, that, in the oncoming eons, He should be displaying the transcendent riches of His grace in His kindness to us in Christ Jesus. For in grace, through faith, are you saved, and this is not out of you; it is God's approach present, not of works, lest anyone should be boasting." (Ephesians 2:4-9)