For as ye in times past have not believed God, yet have now obtained mercy through their unbelief:  (31)  Even so have these also now not believed, that through your mercy they also may obtain mercy.  (32)  For God hath concluded them all in unbelief, that he might have mercy upon all. 

Romans 11:30-32 

Explanation:

The partial and temporary allowance of Israel’s hardening in unbelief of the Gospel has resulted in the gentiles hearing and believing the Gospel.   Ultimately there will be a revival among the children of Israel and they will believe in great numbers again.  God has allowed a temporary and partial unbelief so that his Divine salvation can be heard and believed throughout the world.

We know what God’s will toward the individual:

The Lord is not slack concerning his promise, as some men count slackness; but is longsuffering to us-ward, not willing that any should perish, but that all should come to repentance. 

2 Peter 3:9 

Application:

What God has promised to Israel He will do.  What God has promised to us He will do.  His desire is for His glory, and for the salvation of sinners.  God is working in the course of human history so that people would know and believe in Him.

Response:

We must trust God in all that He does because of who He is.  What is a way that you can trust in God’s plan today?