Paul deals with an objection from his readers - if what he has been saying is true, then hasn’t God rejected His people?
Paul shows that in no way was this the case. God had saved all those He had foreknown - all upon whom He had set His love and for whom He had purposed salvation. The remainder had benefited from His love in many ways but had rejected the truth. They had sought relationship with God but not obtained it because they had sought it on the basis of their works and not God’s grace. God had hardened their hearts so that they would neither see nor hear the truth and turn to Him. This is a solemn warning to the unbelievers - that they should turn today to Christ if they hear His voice and not delay.
We see what a blessing it is for us who are among those to whom God has revealed Himself - what a privilege to be part of the people of God through the election of grace!
We also draw comfort in these days of apostasy and error in the church from the fact that now, as in the days of Elijah, God has a remnant whom He is saving. We need to be about His work in seeking to reach our to these with the Gospel.