Romans 11:31

So, now these [same] Jews have also been disobedient [to God], so that they may also now obtain [God's] mercy by means of the mercy [He has] shown to you [Gentiles].

Romans 10:16

But not everyone [of the Israelites] obeyed [that] good news. For Isaiah said [Isa. 53:1], "Lord, who has believed our message?"

Romans 11:15

For if their rejection [by God] meant that [the rest of] the world could be restored to favor [with God], what would [God's] receiving the Jews back into fellowship be, except like dead people coming back to life?

Romans 11:25

For I want you to know this secret, brothers, so you will not become conceited: Part of the Israelites have become [spiritually] insensitive [to God], [and will remain that way] until the fullness of the Gentiles occurs. [Note: As with verse 12, concerning the Jews, "fullness" here may mean either a large or the complete number of Gentiles who will be saved].

Treasury of Scripture Knowledge

Summary

Even so have these also now not believed, that through your mercy they also may obtain mercy.

Bible References

Believed

Romans 10:16
But not everyone [of the Israelites] obeyed [that] good news. For Isaiah said [Isa. 53:1], "Lord, who has believed our message?"
Romans 11:15
For if their rejection [by God] meant that [the rest of] the world could be restored to favor [with God], what would [God's] receiving the Jews back into fellowship be, except like dead people coming back to life?